More than 600 people are now being investigated in Turkey over buildings that collapsed in the deadly earthquake on 6 February, the government has said.

On Saturday, Justice Minister Bekir Bozdag said 184 suspects - including construction contractors and property owners - had already been arrested.

For years, experts warned that endemic corruption and government policies meant many new buildings were unsafe.

The confirmed death toll in Turkey and Syria has now exceeded 50,000.

Mr Bozdag made the televised remarks from south-eastern Turkey, where the 7.8 magnitude quake struck and was followed by another powerful tremor just hours later.

His comments showed how the investigation had widened - two weeks ago, the authorities said that 113 arrest warrants had been issued.

Among those that have been arrested is a mayor of one of the towns close to where the tremors hit, Turkish media reported.

More than 160,00 buildings collapsed or were severely damaged in Turkey after the quakes, raising questions about whether the natural disaster's impact was made worse by human failings.

Opposition parties and some construction experts accuse President Recep Tayyip Erdogan's administration of failing to enforce building regulations and trying to divert overall blame for the disaster.

They say that government policies have allowed so-called amnesties for contractors who swerved building regulations, in order to encourage a construction boom, including in earthquake-prone regions.

Mr Erdogan has admitted shortcomings, but has appeared to blame fate for the scale of the disaster.

"Such things have always happened. It's part of destiny's plan," he said during a recent visit to the region.

With elections on the horizon, Mr Erdogan's future is on the line after 20 years in power - and his pleas for national unity have gone unheeded.