An unmanned Pakistan naval aircraft crashed in the southern city of Karachi on Tuesday, but there was no damage on ground, police and naval officials said.
"It was a Pakistan Navy UAV (unmanned aerial vehicle) and it was on a routine training sortie when it was hit by a bird," said Pakistan navy spokesman Commander Salman Ali.
The UAV, commonly known as a drone, is used by the navy for surveillance, reconnaissance and photography, he said.
He did not give details on the make and manufacturer of the aircraft.
Senior police official Usman Ghani Siddiqui said the aircraft crashed inside the premises of an oil refinery in Karachi's Korangi neighborhood, but there was no damage.
"There was a small fire but the situation is under control. There were no casualties," he told Reuters.
Pakistan is developing its own drone technology for surveillance and reconnaissance missions because the United States, which is running a bombing campaign with drones in the country's northwest, refuses to give Pakistan the technology.
Two companies in Islamabad, Satuma and East West Infiniti, make drones for the Pakistani military. It is not known if the crashed drone belonged to either company.
The U.S. drone campaign is hugely unpopular in Pakistan, where it is considered a flagrant violation of the country's sovereignty.
The United States has made a series of attacks since 2004 in Pakistan's northwest region as part of its struggle against militancy. According to the New America Foundation, which tracks drone strikes, between 1,561 and 2,461 people have been killed in 254 attacks, mainly in the country's restive tribal regions.
Pakistani officials have criticised them, saying the strikes anger the public and play into the hands of the militants. But strikes that kill high-profile militants would not be possible without Pakistani intelligence, analysts say.