An explosion struck a compound housing foreigners on the outskirts of the Afghan capital Wednesday, Nov 19, and gunfire could be heard immediately afterward, police said, according to the Associated Press.

It wasn't immediately clear if anyone had been wounded.

The blast hit outside the gate of the Green Village in Kabul, the scene of previous attacks targeting the foreigners living there.

Gen. Mohammad Zahir, Kabul's police chief, said gunfire followed the blast but it wasn't clear if the shooting came from inside or outside of the compound. He said security forces surrounded the area.

NATO said it was aware of the ongoing attack, but had no further details.

The heavily fortified Green Village is in an eastern neighborhood of Kabul and houses foreigners working for international service companies. The last attack targeting the compound took place on Oct 13, 2013, when a suicide car bomber killed two passers-by. Another attack there in 2012 killed seven guards and civilians.

This is the second attack on a foreign compound in recent days. On Monday, the Taliban claimed responsibility for a suicide attack on a compound operated by Hart, a security services company. That attack killed two Afghan security guards and three attackers.

Insurgent activity has intensified in the months since President Ashraf Ghani was inaugurated as president and ahead of the withdrawal of foreign forces at the end of the year.