ALGIERS (Reuters) - Algeria's army seized a cache of weapons, including 17 anti-aircraft missiles on Sunday in the southern desert province of Adrar, the defense ministry said.

With Islamic State under pressure in its Libyan stronghold of Sirte, neighboring countries Algeria, Tunisia and Mali are concerned about fighters and arms spilling across their borders. Former Libyan leader Muammar Gaddafi, ousted in 2011, kept huge stockpiles of weapons stashed across Libya.

During Sunday's operation, Algeria's military recovered 17 anti-helicopter missiles, 28 grenades, 27 grenade detonators, one rocket launcher, 20 ammunition magazines and 200 bullets, the ministry said in a statement.

Algeria emerged from a conflict with armed Islamists in the 1990s that left an estimated 200,000 dead. But al Qaeda in the Islamic Maghreb and small bands of fighters allied to Islamic State have been active in remote parts.

(Reporting by Hamid Ould Ahmed; Editing by Raissa Kasolowsky)