Nigeria's government denies that militant Islamist group Boko Haram abducted 500 children.

A former resident said on Tuesday that the militants had taken away about 500 boys when they fled the town earlier this month.

Government spokesman Mike Omeri said the number was lower, but he could not say exactly how many had been seized.

Regional forces recaptured Damasak, a trading town, earlier in March.

Mr Omeri said that the militants released some women and children when they fled the town, but not those "they had married in the period of occupation".

The militants were using them as "protection" and the government had ordered "full military intervention" to secure their release, he said.

Damasak is in Borno state near Niger's border and is about 200km (120 miles) from the state's main city of Maiduguri.