Who controls Libya’s weapons stockpiles?

As Libyan rebels fight for complete control of Tripoli and Muammar Gaddafi vows not to surrender, a question has arisen: who controls the government's weapons stockpiles?

U.S. intelligence and military officials say they fear deadly chemicals, raw nuclear materials and about 30,000 shoulder-fired rockets could fall into the hands of insurgents as Libya faces a power vacuum, the Associated Press reports.

(More from GlobalPost: In Libya, party gives way to concern for future)

Officials worry that militant groups like Al Qaeda could seize control of the weapons as the rebels battle for Tripoli or that Gaddafi, as defiant as ever, could use the weapons to make one last push to stay in power.

British Foreign Secretary William Hague has also warned that Gaddafi could use the weapons, the Telegraph reports.

“You can’t anticipate everything the Gaddafi regime will do. They are a vicious regime,” he reportedly said. "They are in their death throes. There are people still out there. That’s why we can’t rule out any of those things.”

(Earlier on GlobalPost: Libya rebels celebrate inside Gaddafi compound)

A U.S.-backed disarmament pact reportedly left the stockpiles in Gaddafi's control.

"U.S. and allied officials say chemical and nuclear stockpiles appear to be still under the control of what's left of the Libyan government despite rebel military advances into the capital. That may or may not be reassuring. It depends on whether Gaddafi loyalists, increasingly desperate, adhere to international agreements not to use or move the material," AP reports.

The U.S. State Department says it is working to ensuring governing forces in Libya have control over the weapons, but some U.S. officials are questioning what will happen if Libyan security forces flee, it states.

Meanwhile, Gaddafi vowed "martyrdom or victory" in an audio message delivered while in hiding from rebel forces and broadcast on a local Tripoli radio station on Wednesday. Gaddafi said he would fight to the last drop of blood against the "aggression."

The address came hours after rebel forces stormed Gaddafi's Bab al-Aziziya compound in Tripoli.