An "extremely loud" explosion has been reported in Madrid's city centre - with rescue teams, firefighters and police sent to the scene.
Spanish media reports said the explosion took place in a building near a nursing home - and videos and images shared on social media showed rubble scattered in the street.
"We didn't know where the sound came from. We all thought it was from the school. We went up the stairs to the top of our building and we could see the structure of the building and lots of grey smoke," a witness told the AP news agency.
According to TVE, several people have been injured, while Telemadrid is reporting that at least one person is trapped.
On Wednesday, at least four people killed by an explosion at a residential building located in Central Madrid, Spain.

Eyewitnesses reported a strong smell of gas shortly before the blast.  The building was owned by a Roman Catholic Church and was destroyed by the blast.  Among the dead was an electrician who was present to inspect the building's boilers.



At least ten others were injured as a result of the incident.  According to the reports, strong gas smell had first been detected at around 2pm local time, so an electrician David Santos Muñoz had been called out to inspect the boilers.  Minutes after this, at 2:56 pm, the building exploded, killing him and at least three others.  An owner of a nearby bar told '''' "It was as if a bomb had dropped, the noise was tremendous".  An eyewitness also told the newspaper "it was like an earthquake; I thought a bomb had gone off."

A school and nursing home were nearby to the blast, the latter of which had suffered minor damage according to the city's mayor .  Nobody was injured in either of these and TVE said that the school has been said to have been empty at the time due to closures after significant snowfall in the capital.  Police said the nursing home was safely evacuated following the blast.