ISLAMABAD, Sept. 1 -- Emergency has been declared in Pakistan's southern port city of Karachi as heavy monsoon rains continued to lash the city on Thursday, local reports said, adding that the local government has requested the Pakistani army for assistance.

The army has arrived at various parts of the city to assist the local government in rescue and disaster relief operation, according to the ARY News.

The army was instructed to extend full support to Karachi city administration and water extraction pumps have been provided to the city, according to the military's media wing of the Inter-Services Public Relations.

Local reports said at least 16 people were killed, mostly due to electrocution. Parts of the city have been submerged, while road and railway traffic were also affected by the heavy rainfalls.

According to Pakistan Meteorological Department, widespread rain, thundershowers with moderate to heavy rainfalls may occur in the city in next 24 hours.

This is the second wet spell which hit the country over the past 10 days. At least 22 people were killed and several others injured in the spell on Aug. 20.