Fourth senior Mexican police officer shot dead

MEXICO CITY, May 8 (Reuters) - A group of men shot dead a high-ranking Mexican federal police officer involved in the government's war on drugs on Thursday, the fourth senior policemen killed in recent days.

Regional commissioner Edgar Millan was gunned down in the capital in the early hours of the morning, a spokesman for the Security Ministry told Reuters. He was shot nine times, the spokesman said.

"They were hunting him," he said. The spokesman said it was too early to say if the murder was drug-related.

Millan was in charge of coordinating large scale operations to break organized crime rings, including drug trafficking. He had previously worked for Mexico's elite police squad as well as for the country's intelligence agency CISEN.

Violence across Mexico has been on the rise despite President Felipe Calderon launching an army-backed fight against drug smuggling in Dec. 2006.

Last year, there were more than 2,500 drug killings across Mexico. So far this year, there have been more than 1,100.

Earlier this week, drug hit men killed Saul Pena, a senior police officer in Ciudad Juarez, even though the army has staged a large deployment in the violent city across the border from El Paso, Texas. Pena was due to be named one of city's five police commanders.

Last week, two other senior policemen were killed in Mexico City.

(Reporting by Anahi Rama and Cyntia Barrera Diaz, editing by Vicki Allen)