A massive explosion occurred in the northern Pakistani city of Sialkot, media reports said on Sunday.

The sound of the blast was reportedly heard near the cantonment area in the Punjab province.

"Pakistan - Multiple explosions at the Sialkot military base in northern Pakistan. Initial indications are this is an ammunition storage area. A large fire is burning. Cause as yet unverified," Rishi Suri, editor of The Daily Milap said in a tweet. -- ANI