Heavily-armed gunmen mounted a brazen attack near the Karachi international airport, within a day of a terror siege there that ended in a toll of 30, media reported.

The militants later fled from the targetted Airport Security Force (ASF) Academy's camp after a brief gun battle, Dawn Online reported.

The attack on the ASF Academy's camp number 2, near Karachi's Jinnah International Airport, took place within a day of an audacious strike Sunday night at the Karachi airport, in which 20 people and 10 militants were killed.

An official confirmed that there were no casualties in the new attack. He also said that the airport was secure and operations have resumed after a brief suspension.

Inter-Services Public Relations (ISPR) spokesperson Asim Bajwa posted on Twitter that the "chase is still on".

The official said two attackers opened fire near the ladies hostel near D gate, which is located behind the ASF camp.

"The ASF checkpost is about 100 metres from the scene. We were informed of the incident by our sentry posted there," the official said.

The number of attackers could be between four and seven, he added.

A Twitter account suspected to be operated by the Tehreek-i-Taliban Pakistan (TTP) Mohmand faction tweeted Tuesday claiming that the group has carried out this second attack.

The TTP also claimed responsibility for Sunday's attack.

The ASF was established in 1976 after a Pakistan International Airlines flight was hijacked in March 1981 and is part of Pakistan's Aviation Division and is responsible for the protection and safety of the airports and the aircraft.

It works towards protecting the civil aviation industry against unlawful interferences, adopting counter-terrorism measures, preventing crime and maintaining law and order within the limits of airports in the country.