ISLAMABAD, April 22 (Xinhua) -- A week-long ban has been imposed in Pakistan's southern port city of Karachi on the use of drones due to "security threats to vital installations" by anti-state elements and hostile agencies, the local authorities said on Monday.

The decision came after the police requested a ban in the wake of recent attacks on foreigners in the South Asian country, an official notification of Commissioner Karachi Division said.

"In order to avoid any untoward incident and for the safety and security of vital installations, there are sufficient grounds to proceed" with a ban on the use of drones under the law, it added.

The decision has been in place "with immediate effect," the notification said, adding that the police have been authorized to register complaints against the violation of the law.

At least two terrorists were killed and three others injured on the morning of April 19 in an attack on a convoy of foreign nationals in Pakistan's southern port city of Karachi, police told Xinhua.

Senior Superintendent of Police in Karachi's Malir district Tariq Mastoi said that two terrorists attacked a convoy carrying five Japanese in Mansehra Colony area in Landhi Town region of Karachi but retaliatory firing from security guards foiled the attempt.

（Editor:Fu Bo）