Baltimore police are searching for a man who is charged in a warrant with severely beating a city officer who was answering a routine drug call on Pennsylvania Avenue last month, a department spokeswoman said.

Ellis D. Johnson, 26, of the 600 block of Mosher St. is charged with attempted first-degree murder, first- and second-degree assault, and attempting to disarm a law enforcement officer.

Officer Nicole Monroe, the spokeswoman, said the incident occurred about 7 p.m. Jan. 14 as Officer William Olsen, 33, who has been on the force less than year, responded to a report of suspected drug dealing at an apartment in the 1500 block of Pennsylvania Ave.

Olsen, assigned to the Central District, went into the apartment building, walked up to the second floor and "realized that he interrupted some sort of drug transaction," Monroe said.

The spokeswoman said three teenagers threw items at the officer, yelled that the officer was alone and began to beat him and try to get his weapon. Monroe said that a man "began to beat him in the head with a blunt object."

Monroe said Olsen was able to call for help before falling unconscious. Police said three teens were arrested near the building and charged as juveniles. Detectives later learned the name of the adult suspect, who frequents Pennsylvania Avenue, Monroe said.

Monroe said Olsen was treated at Maryland Shock Trauma Center, has been released and is recovering at home. He has nerve, neck and shoulder injuries, and will require hip surgery, Monroe said.