Sudanese activists on social media websites criticized the government for placing a factory with such large quantities of ammunition in a residential area.
Sudan has been engaged in various armed conflicts for many years.
Sudan's government has been at war with rebels in the western region of Darfur and with its neighbors in South Sudan, which broke away to become Africa's newest country in 2011. Sudan's president, Omar al-Bashir, has been indicted by the International Criminal Court on charges of genocide, war crimes and crimes against humanity.
Sudan was a major hub for al-Qaida militants and remains a transit for weapon smugglers and African migrant traffickers.
In 2009, a convoy carrying weapons in northeastern Sudan was targeted from the air, killing dozens. It was widely believed that Israel carried out the attack, hitting a weapons shipment headed for Palestinian militants in the Gaza Strip. Israel never confirmed or denied that. Sudanese parliamentarians denied that weapons were transported in the area.
Israel never confirmed or denied it was responsible for the attack.
The U.S. imposed economic, trade and financial sanctions against Sudan in 1997, citing the Sudanese government's support for terrorism, including its sheltering of al-Qaida founder Osama bin Laden in Khartoum the mid-1990s.
In 1998, American cruise missiles bombed a Khartoum pharmaceutical factory suspected of links to al-Qaida. That followed the terror group's bombings of U.S. embassies in Kenya and Tanzania that killed 224 people.
The Yarmouk weapons complex was built in the 1996. Sudan prided itself in having a way to produce its own ammunition and weapons despite international sanctions.
Yarmouk is one of two known state-owned weapons manufacturing facilities in the Sudanese capital.
Jonah Leff of the Geneva-based Small Arms Survey told The Associated Press that the location of the two factories is "certainly a hazard" to Khartoum's population if the weapons inside are not properly maintained or secured.
A September report from the Small Arms Survey said there was evidence from weapons packaging found in Darfur and in South Kordofan that arms and ammunition from China are exported to Yarmouk and then transported to the two embattled regions.
Leff said that although the Small Arms Survey has documented Sudanese military stocks of Iranian weapons and ammunition, there is no evidence that Iranian weapons are being assembled or manufactured in the two Khartoum factories.
Associated Press writers Maggie Fick and Sarah El Deeb contributed from Cairo and Michael Astor from the United Nations.
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