The gruesome killing of a 19-year-old college student in Kerala's Kochi on Sunday midnight has brought some of the most dreaded radical political organisations in the state back to focus. The killing of Abhimanyu inside the college campus bears the hallmarks of the dreaded NDF operation, the SFI has said.

The police, who have arrested three people, have said the murder was carried out by criminal gangs from outside the college. The three arrested are workers of the Social Democratic Party of India (SDPI), the political wing of the Popular Front of India. The Popular Front itself descends from the dreaded NDF and shares the ideological fountains of the banned SIMI.

The police said the arrested persons had accompanied students from the Campus Front of India (CFI), the student wing of the Popular Front of India (PFI), into the college campus after the latter picked up a fight with the slain SFI worker and his friends. Police have launched a massive manhunt for 15 more suspected gang members.

Earlier, Kerala Chief Minister Pinarayi Vijayan, speaking in the state assembly, said the killer gang, which stormed into the campus after midnight and knifed three degree students, had comprised former members of NDF.

NDF, or the National Democratic Front, is a Kerala-based hardened Islamist organisation and a precursor of the politically organised Popular Front of India (PFI).

Here's look at the murder, the perpetrators and the complex web of organisations that they allegedly came from:

Murder of Abhimanyu, a 19-year-old from a backward region

Abhimanyu, a second-year degree student at one of the most ancient colleges in Kerala, came from a backward region and from a disadvantaged social background. He was a rising star of the SFI in Ernakulam Maharajas college, the legendary hotbed of student politics in the state.

His life was snuffed out after an apparent tussle over sticking posters on the campus. The CFI activists had apparently objected to the SFI students from sticking posters in an area reserved by them eerier. After the fight had died down, criminal gangs with alleged links with terror-related outfits entered the campus after midnight. While one of them held Bahaman's arms, another stabbed him in the chest, killing him instantly. Two other students also were stabbed and one of them is in critical state.

Who killed Abhimanyu?

The SFI says Abhimanyu and friends were stabbed by members of the NDF, a banned outfit. After NDF was banned it made a reappearance in the form of the Popular Front of India.

"A group of NDF activists came from outside attacked the college students with deadly weapons. Another comrade also has been severely injured and hospitalized in critical state. Red Salutes to our beloved Comrade," SFI, the student wing of the ruling CPI-M said in a statement.

Abhimanyu was a student of B.Sc Environmental Chemistry and he halide from the backward Vattavada region in Idukki district.

What is Campus Front of India?

The organisation was launched in 2009 in Kerala. It claims it is a "neo-social student's movement, which aims to empower the campuses by developing a new generation of activists." Operating mainly in Kerala and Karnataka, the student organisation had run campaigns against college rules that prohibited headscarves on the campus, and other similar issues.

Another campaign it ran, according to its website, is 'Jerusalem belongs to Palestine, in Solidarity with Intifada."

What is NDF?

The National Democratic Front was formed in Kerala in 1993 with a stated mission to "focus on socio-economical issues of minorities giving a focus to Kerala Muslims in Kerala". The outfit, which clashed with the RSS and the CPI-M in Kerala for years, then merged with the Popular Front of India in 2006.

One of the most violent communal incidents the outfit was involved in was the slaughter of Hindus on Marad beach in 2002. The BJP had alleged that NDF had links with terror outfits in Pakistan. Kerala CM Pniarayi Vijayan also called the organisation a terror outfit. However, NDF has said it did not have a role in the murder of 8 Hindus in Marad and that it was a conspiracy hatched by the RSS.

A Frontline investigation revealed that the organisation created fear in ordinary Muslims and pushed for the implementation of a sharia code. The outfit was also accused of attacking moderate Muslims.

What is Popular Front of India?

The Popular Front was formally organised in 2006 in Kerala, but it was seen as the natural offshoot of the NDF, which took shape in the era of insecurity that followed the Babri Masdij demolition in 1992. THE PFI was an amalgam of hardliner organisations that took shape during this period in the states of Kerala, Karnataka and Tamil Nadu. Karnataka Forum for Dignity and Manitha Neethi Parasai in Tamil Nadu were some of the outfits that merged with NDF to form PFI.

"The dalits, the tribals, the religious, the linguistic and cultural minorities, the backward classes and the women are denied their cultural and social space, making India one of the most backward areas in the world," the PFI says in its website.

However, the organisation has been accused of hardliner activities such as links with Islamic terror groups, possession of arms and training in weaponry, hate campaigns and 'love jihad'.

Earlier this year, one of the alleged founders of the movement said that PFI, in its current form, has deviated from the original goals.

Rashid Abdulla, a Kerala-based Isis operative supposed to be living in Afghanistan, said in May that the NDF was formed to wage Jihad against the oppressors of Muslims including the CPM and the RSS, the ToI reported.

However, after the NDF merged with PFI, there was a dilution in its mission, said Abdullah, in one of the voice messages released from Khurasan province in Afghanistan.

The Isis operative even said that the current leadership of the PFI is doing 'spy work" for the police. "They are identifying IS supporters and possible recruits for the IS to help the Kaffir government," he said, according to the ToI report.

What's the SIMI connection?

In 2012, the Kerala police said the PFI is the new face of banned extremist outfit Students Islamic Movement of India (Simi). In a statement submitted to the Kerala High Court, the police said PFI was engaged in anti-national activities.

The SIMI, which was established in 1977 in Aligarh, was termed a terror outfit in the later decades and was banned at various points. The first time a ban was imposed on SIMI was in 2001. Latest, the student outfit was outlawed in 2014 by the UPA government for five years.

In 2012, the Kerala government told the High Court that the NDF was a direct offshoot of the banned SIMI. The ideology of NDF and other hardliner organisations is the same as that of Simi, Siddique Rawther, then additional DGP of Intelligence, told the court, according to the Times of India.

What is SDPI?

The Social Democratic Party of India (SDPI), which was founded in 2009, is the political wing of the Popular Front of India. SDPI has fielded candidate in elections in the southern states and its activists have been in violent confrontations with those of the BJP.

The National Investigation Agency (NIA) had named an SDPI worker in the love jihad case that rocked Kerala earlier this year. According to a report in the Hindu, the main accused in the love jihad case, Shefin Jahan, was an active member of SDPI and had criminal cases against him, the NIA said. Shefin is the husband of Akhila, who converted to Islam and took the name of Hadiya.

SDPI's website says it's "party founded for the advancement and uniform development of all the citizenry including Muslims, Dalits, Backward Classes and Adivasis. Its objective is to share the power fairly among all the citizens."

The site was last updated on May 18 and leads with the story -- 'Shifting US Embassy to Jerusalem is against the Consensus of Palestinians'.