The Afghan police investigator who made the only arrest in connection with the killing last year of Canadian diplomat Glyn Berry in Afghanistan now fears retribution for his police work and is appealing to Canada for protection.

Capt. Sher Ali Farhad has fled with his family from Kandahar and has sought safe haven in Kabul after receiving death threats and learning on Saturday that the suspect he locked away is now a free man.

Pir Mohammed, seen here, has been arrested and released in the past.
(CBC)

"My reaction, of course, is that I'm worried," Farhad told the CBC through an interpreter. "I feel like I'm in danger."

Police had twice arrested Pir Mohammed, most recently in December 2006 for attempting to pass through a Kandahar City checkpoint in a car flagged by Afghan intelligence as a potential bomb threat.

He was detained for the first time in early 2006 after police found a rocket-propelled grenade launcher, a Kalashnikov rifle and a picture of a Taliban leader in his home, but Mohammed walked out of prison two days later because influential tribal leaders persuaded authorities and Kandahar's governor to release him.

Farhad believes Mohammed's connections to those powerful tribal leaders in Kandahar could endanger him and his family. He is seeking protection or even asylum in Canada.

Afghan National Police chief Asmatullah Alizai also urged Canada and other countries to heed his officer's request for help, saying it would "send a positive signal that with the problems we face here, the international community is supporting us."

Still, Farhad is far from being the only police officer seeking help from Canada because of his efforts to bring law to his country, and officials at the Canadian Embassy in Kabul have so far refused to comment on his case.

For the time being, Farhad said he is on the run — moving often from shelter to shelter.

"I am just living one week at one friend's house, one week in another, just a few days in each place," Farhad said.  "It's too dangerous for us to stay in one place for too long. I am living like a refugee in my own country."

Last month, in an exclusive interview with the CBC, Mohammed maintained he played no part in the January 2006 suicide car bombing that killed Berry, the 59-year-old Canadian envoy. Mohammed said the minivan used in the attack, which was last registered under his name, was sold before the bombing, although he admitted he had no documents to prove the sale.

Three Canadian soldiers were also wounded in the same attack.