Burundi environment minister Niyonkuru shot dead

Emmanuel Niyonkuru was on his way home when he was shot

Burundi's environment minister has been shot dead while on his way home on New Year's Eve.

Emmanuel Niyonkuru, 54, was killed at about 00:45 local time (22:45 GMT) by "a criminal with a gun", a police spokesman tweeted.

Tweets from Pierre Nkurikiye said a woman who was with Mr Niyonkuru had been detained for questioning, following the "assassination".

Burundi's President Pierre Nkurunziza said the crime would not go unpunished.

Hundreds of people, including high-ranking army officials, have been killed in unrest since President Pierre Nkurunziza ran for a third term in 2015, a move which opponents said was unconstitutional. But this is the first time a serving government minister has been killed.

For months the country had been relatively calm.