Michoacan is a key battleground in the government's war on the drug trade
Eleven Mexican soldiers have been killed in a helicopter crash during anti-drug operations in the western state of Michoacan.
The Bell 212 helicopter went down around midday (1800 BST) near Uruapan. Eyewitnesses said they heard the engine cut out as it tried to land.
Police have cordoned off the crash site and forensic officers are sifting through the wreckage.
Michoacan is a major flashpoint in the government's war against drug cartels.
"There are 11 men dead, including a colonel, and one soldier was injured," said a spokesman for the state attorney general's office.
"The motor stopped and the helicopter plummeted to the ground," said local resident Agustin Vargas.
Drug-related violence has become a serious issue across Mexico and since taking office in December 2006, President Felipe Calderon has sent some 25,000 soldiers and federal police to key areas to tackle the drug traffickers.
Michoacan's hills and avocado fields are said to hide methamphetamine, or "crystal meth" labs, and landing strips for planes moving cocaine to the United States.
German air ambulance is similar to the military variant that crashed.
Eleven people have died after a military helicopter crashed during an anti-narcotics flight in Western Mexico. The Bell 212 went down near Uruapan in Michoacan.

Michoacan is a major area in Mexico's anti-narcotics operations, which are conducted by the nation's military. The rotorcraft went down around midday. Police cordoned off the scene and forensic officers have moved in to examine the site. The Defense Department is investigating.

A statement by the military confirmed the crash. "There are 11 men dead, including a colonel, and one soldier was injured," said a state attorney general's office spokesman. The wounded soldier, who was the sole survivor, was flown to a Mexico City military hospital, and remains there in a serious condition.

Although authorities released no crash details, witnesses say the helicopter lost power during attempts to land. "The motor stopped and the helicopter plummeted to the ground," said one local resident named Agustin Vargas. The flight had been headed to a marijuana field with the intention of raiding it.