Top officials of Tanzania’s main opposition party, Chadema, have been arrested in the capital Dar es Salam.

It is not entirely clear why the party's national chairman Freeman Mbowe and other senior officials are being detained.

However, the opposition officials have been reporting at Central Police station for questioning in connection with 16 February demonstrations in the city.

This comes in the wake of the Sunday warning by the influential Lutheran church about the shrinking democratic space and muzzling of the media by the state.