New president Adama Barrow arrives in the Westfield area of Serrekunda in Gambia (AP/Sylvain Cherkaoui)

The Gambia official accused of overseeing the torture of prisoners under former leader Yahya Jammeh has been arrested, police in Senegal say.

Borra Colley was arrested on Wednesday while trying to make his way to Guinea Bissau, a statement said.

He had been director of the notorious Mile Two prison.

He also led the Jungulars, Mr Jammeh's personal military of some 50 officers who reportedly went into exile with him last weekend in Equatorial Guinea.

Some former Gambian officials fled the country during the political crisis that ended this week with the arrival of new president Adama Barrow.

AP