By Gul Yousufzai and Saud Mehsud
QUETTA/DERA ISMAIL KHAN, Pakistan (Reuters) - The brother of a man killed alongside Afghan Taliban chief Mullah Akhtar Mansour in a U.S. drone strike in southwest Pakistan has filed a report with police asking for his brother's killing to be investigated, officials said on Sunday.
Muhammad Azam, a Pakistani citizen, was driving Mansour from the Pakistan-Iran border to Quetta, capital of Pakistan's Balochistan province, when a U.S. drone destroyed the car in the Koshki area of Noshki district, killing them both.
Azam was a regular taxi driver on the route and was not connected to the Taliban, his brother Muhammad Qasim said in a police report seen by Reuters.
The "First Information Report" filed by Qasim would form the basis of any police investigation into the drone attack.
Drone attacks outside Pakistan's tribal areas, such as the one that killed Mansour and Azam, are rare.
Much of the country's Islamist militancy is based in the tribal areas of northwest Pakistan. Critics of drone strikes allege there has been a tacit agreement between Islamabad and Washington allowing strikes in some tribal areas but not elsewhere. Pakistan denies that any such agreement exists.
The report was filed by Qasim on Wednesday, local official Muhammad Omar told Reuters on Sunday night.
It does not name Mansour, identifying him only as Muhammad Wali, an identity he had been using while in Pakistan, complete with identification documents and a passport.
Pakistani authorities confirmed for the first time on Sunday that it was indeed Mansour who was killed in the drone strike.
"He was identified after conducting a DNA test which showed a match with a close relative of Mullah Mansour's, who had come to Pakistan from Afghanistan to receive the body," said an interior ministry statement.
The police report filed in Balochistan notes that the United States has claimed responsibility for carrying out the attack. No individuals or officials are named as suspects.
A U.S. embassy spokesman in Islamabad declined to comment, referring all questions on the subject to Washington.
"My brother was innocent. And he was extremely poor. He has four young children. He was the sole breadwinner in his house," Qasim told police, according to the report.