MANILA (REUTERS)- The Philippines' national police chief said on Tuesday (Aug 23) about 300 of his officers were suspected to be involved in the drugs trade, warning these personnel will be removed and charged in court if found guilty.

Director-General Ronald dela Rosa said about 300 police officers were on a watch list on suspicion of selling drugs confiscated in raids or protecting syndicates involved in the manufacture and distribution of narcotics.

He also told a Senate hearing there was no declared policy to kill drug users and pushers.

In addition, he said not all of the 1,067 unexplained killings being investigated during a crackdown on illegal drugs, which began seven weeks ago when President Rodrigo Duterte took power, were drug-related.

Some of those killings had been the result of personal grudges or robbery, although most of them were still being investigated and could be drug-related, he said.

"Not all deaths under investigation are drug-related," dela Rosa said.

The United States, a close ally of the Philippines, said overnight it was "deeply concerned" by the reports of the killings and the State Department urged Duterte's government to abide by human rights norms.