BELGRADE (Reuters) - Serbia's defense minister on Thursday ordered urgent security checks at all weapons depots after dozens of semiautomatic handguns, five assault rifles and two crates of ammunition went missing from a storage site in Belgrade.

It was unclear whether the incident had any connection with the Interior Ministry's seizure on Wednesday of an arms cache including over 100 grenades and 30 kg (65 pounds) of explosives and the arrest of 10 people.

It was the biggest such haul for 15 years in a country where many automatic and anti-tank weapons remained in private hands, often organized crime gangs with shadowy government links, after the end of the 1990s Yugoslav conflict.

Some of the assault rifles used by Islamist militants who

killed 130 people in Paris a year ago came from former Yugoslavia's 1980s state arsenal.

"In one of the depots in Belgrade garrison, 70 semiautomatic handguns, five assault rifles and two crates of ammunition were missing," the Defence Ministry said in a statement.

It said Defence Minister Zoran Djordjevic ordered an urgent inspection of all warehouses with weapons and equipment.

The ministry also said "significant funds" from the 2017 defense budget would be devoted to improving security at state depots that still hold a significant quantity of arms left over from the old communist Yugoslav federal army.

(Reporting by Aleksandar Vasovic; Editing by Mark Heinrich)