Pictures have been posted on social media showing an arrest being made after deadly shootings in New Zealand.

Forty people have been killed and more than 20 wounded in attacks at two mosques in Christchurch.

New Zealand prime minister Jacinda Ardern called it one of New Zealand's "darkest days".

Police Commissioner Mike Bush confirmed that four people were in custody, but said it was unclear if others were involved.

Witnesses told local media they ran for their lives, and saw people bleeding on the ground.