A man has been arrested in Nigeria as he tried to smuggle hand grenades and rifle ammunition into the information ministry in Abuja, authorities said.

"We arrested him with black bags containing three hand grenades and 37 live [rounds of] munitions. We snatched the bag from him at the gate as he was entering the compound," security officer Akindele James told Reuters.

According to some reports, the man managed to get through the gate of the Radio House compound and was apprehended as he headed inside the building, where two ministers - aviation minister Stella Oduah and youth minister Bolaji Abdullahi - were conducting a news conference.

The state-run Nigerian Television Authority showed footage of the man sitting on the ground next to the grenades and ammunition after his arrest. He said he was supposed to hand the bag of items over to someone at the news conference.

Despite the incident, the news conference, which was aired live on state television, continued uninterrupted.

Police later said the man had been identified as John Akapapu.

Authorities are trying to establish whether why he was carrying the weapons and if he was working for a particular group.

The person whom he was allegedly supposed to hand the cache of weapons to has yet to be formally identified.

Nigeria has become under increasing attacks by the radical Islamist sect Boko Haram.

The group wants to impose Sharia (Islamic law) law across Nigeria, a country divided between a mainly Muslim north and a Christian south.

While Boko Haram has conducted a series of deadly bombings across the country, it has previously used car bombs rather than attackers armed with hand grenades.