Updated

MORELIA, Mexico -- Mexico's federal police detained nearly 50 members of two major drug cartels, including suspects in the recent armed attack on a police helicopter, authorities said Saturday.

The suspects include 36 members of the La Familia cartel and 10 members of the Zetas drug gang, the federal police said in a statement.

La Familia gang members were detained in connection with the attack on a federal police helicopter Tuesday that wounded two officers and forced the craft to land. The statement said 11 other alleged cartel members were killed during the operation Friday night in the Pacific Coast state of Jalisco.

Authorities added that the 10 Zeta members were detained Friday at a ranch in Cancun, where a kidnapping victim was found and released.

Along with the 36 La Familia members, police seized over 70 rifles, 20,000 weapon cartridges, three grenades and 14 handguns in an air and land raid that left two officers injured.

Federal Police Commissioner Facundo Rosas said the mass detention has delivered a blow to a top leader of La Familia, Jose de Jesus Mendez Vargas, the alleged leader of the detained suspects.

"His group has been weakened, which is why we don't rule out the possibility that (Mendez Vargas) will look to other criminal organizations for support," Rosas said during a news conference.

Rosas said Mendez Vargas is locked in a confrontation with The Knights Templar, a rival faction of La Familia. The Knights' split from the cartel is believed to be the source of a recent surge in violence in the western state of Michoacan.

The increase in cartel firefights and clashes with police in the state prompted frightened villagers to flee outlying hamlets and seek shelter in town centers earlier this week.

Since then, all 3,500 rural residents who had sought refuge in churches, schools and recreation centers in Apatzingan and Buenavista Tomatlan have returned home, said Michoacan state Civil Defense Director Carlos Mandujano. The makeshift shelters were dismantled Saturday, he added.

However, 1,000 federal police and armed forces deployed earlier in the week to patrol trouble spots and calm fears will stay at their posts until further notice, military authorities say.

In a separate incident, an Air Force helicopter crashed Saturday near the same violence-plagued Michoacan city of Apatzingan where the first helicopter had been shot on Tuesday, the Defense Department said in a statement.

This time, however,the crash was an accident caused by apparent mechanical failure and is being investigated, the Defense Department said. The pilot and co-pilot suffered minor injuries when the chopper went down in a wooded area shortly after lifting off from a local Army base.