The fire at a Sudanese weapons factory.

New evidence from satellite photos of a weapons factory in Sudan that the country alleges was bombed by Israel indicates that the site was hit by an airstrike, according to a U.S. monitoring group.

Pictures released by the Satellite Sentinel Project (SSP) showed six 16-meter wide craters near the epicenter of the explosion that occurred Oct. 24.

Military experts consulted by SSP found the craters to be “consistent with large impact craters created by air-delivered munitions,” SSP spokesman Jonathan Hutson told the Associated Press.

The Israeli government has neither confirmed nor denied involvement. However, Israeli officials have long noted that Sudan is a major transit site for weapons shipments from Iran to its proxies Hamas and Hezbollah as well as for al-Qaeda militants.

“[Sudan is] used as a base to disseminate terror, in Africa and in our direction too,” said Israeli Vice Prime Minister Moshe Ya’alon.

Sudan’s President Omar al-Bashir has blamed Israel for the attack and promised retaliation.

“We will not sit idly by while Israel continues to attack us,” Bashir said over the weekend, “Sudan reserves the right to strike back at Israel,” he added.

This incident is not the first time Israel has been accused of military involvement in Sudan. In early 2009 Israel was suspected of carrying out three airstrikes against weapons convoys in Sudan. In 2011, Sudan blamed Israel for a missile strike in Port Sudan on a vehicle reportedly carrying a top Hamas arms trafficker.

Sudan has a long history of involvement in human rights abuses and terrorism. Bashir has been indicted by the International Criminal Court (ICC) on charges of genocide, war crimes and crimes against humanity for his involvement in Darfur. The Sudanese government also gave shelter to al-Qaeda founder Osama bin Laden during the 1990s. In 1998, the U.S. bombed a pharmaceutical factory in Khartoum that had links to al-Qaeda.