Israeli Prime Minister Benjamin Netanyahu declared Thursday the nation's military will stop at nothing to destroy all of the tunnels the Palestinian militant group Hamas uses to sneak across the Gaza border into Israel.

"We have neutralized dozens of terror tunnels and we are committed to complete this mission, with or without cease-fire," Netanyahu said according to Fox News. "Therefore I will not agree to any offer that does not allow the military to complete this important mission for the security of the people of Israel."

Israel said it will take a few more days until all of the tunnels are demolished. So far most of the 32 tunnels found have been destroyed.

The prime minister's remarks came after Israel's military announced it has called up 16,000 reservists to beef up its now 23-day offensive against Hamas in the Gaza Strip. The extra troops were called to lessen the strain on troops already fighting in the strip, an Israeli defense official told the Associated Press on condition of anonymity.

Israel has also asked the U.S. for more ammunition. A U.S. defense official confirmed to CNN, also on the condition of anonymity, the U.S. agreed to send several types of ammunition, including 120mm motor rounds and 40mm for grenade launchers.

The U.S. is also expected to send rounds for tanks. However, defense officials later told CNN the ammunition was not included in the shipment.

Israel now has a total of 86,000 reserve troops battling Hamas in the offensive that began July 8. A total of 56 Israeli soldiers, two Israeli civilians and a Thai worker have so far been killed, according to Fox News.

Palestinian health officials say 1,360 Palestinians, mostly civilians, have been killed since the beginning of the offensive. Israel has been accused of not doing enough to ensure Palestinian civilians in Gaza are not harmed, especially after 17 people were killed when tank shells struck a U.N. school housing refugees in Jebaliya, Gaza, on Wednesday.

Mark Regev, spokesman for the Israeli government, told the BBC they will apologize if shells from Israeli tanks indeed struck the school.

"We have a policy; we don't target civilians," Regev said. "It's not clear to us that it was our fire, but we know for a fact there was hostile fire on our people from the vicinity of the school."