Nine more people have died of their injuries following last week's fire at a Romanian nightclub, bringing the number of deaths to 41, officials say.

Seven people died in hospitals in the capital Bucharest, while another two passed away in the Netherlands, where they had been treated.

The blaze at Bucharest's Colectiv club on 30 October was started by fireworks.

It led to mass protests and the resignation of the government led by Prime Minister Victor Ponta.

Three owners of the club have been arrested amid allegations that the venue was overcrowded, lacked the required number of emergency exits, and may not have been authorised to hold such a concert.

More than 100 people are still being treated, with dozens still in critical condition.

Concerns that safety at the club was compromised because of corruption - a long-standing issue in Romania - have further fuelled public anger against the political elite.

Thousands of protesters held a rally in Bucharest late on Friday - for the fourth consecutive day.

President Klaus Iohannis has called for a "sea change" in Romanian politics in the wake of the government resignation.