Cairo (AFP) - Egypt's army said Sunday it has destroyed 13 more tunnels connecting the Sinai Peninsula to the Gaza Strip, taking to 1,639 the overall number it has laid waste to.

Cairo has poured troops into the peninsula to counter a rising insurgency since the ouster of Islamist president Mohamed Morsi last year, and its security operation involves the destruction of these tunnels.

The Palestinian militant group Hamas, which is the main power in Gaza, reportedly uses the tunnels to smuggle arms, food and money into the blockaded coastal enclave.

Israel has been waging a military offensive on Gaza since July 8 to halt rocket fire, and it launched a ground assault on July 17 aimed at destroying the network of tunnels.

It accuses Hamas of using the tunnels to attacks on Israel.

Ties between Hamas and Cairo have deteriorated since the Egyptian army deposed Morsi on July 3, 2013. Hamas is an affiliate of Morsi's Muslim Brotherhood.

Cairo also accuses of Hamas of being involved in militant attacks inside Egypt, which have multiplied since Morsi was toppled.

Militant groups say their attacks are in retaliation for a police crackdown on Morsi's supporters. The crackdown has seen more than 1,400 people killed in street clashes.