A militant group affiliated to Islamic State (Isis) has claimed responsibility for a wave of suicide bombings targeting Shi'ite mosques in Yemen.

At least 137 people were killed and 345 others injured as five attackers blew themselves up at two religious sites in the capital, Sana'a, during Friday midday prayers, traditionally when the mosques are busiest.

After the attack a group calling itself the Sana'a Province of the Islamic State posted a message online calling responsibility for the massacre.

Charlie Winter, a researcher for the London-based counter-extremism Quilliam Foundation Think Tank, tweeted:

The Sunni extremist group described the bombing at the Badr and al-Hashoosh mosques as a as a "blessed operation" against the "dens of the Shi'ites."

The claim, which could not be immediately verified was posted on the same website used by IS to take credit for the shooting at a museum in Tunisia on 18 March.

In November 2014, IS self-styled Caliph Abu Bakr al-Baghdadi used an audio message to call for jihadists to carry out attacks against Muslim Shi'ite across the Middle East before to move on to bringing war to the West.

Initially, fingers were pointed at IS's rival jihadi group al-Qaeda that has a strong presence in Yemen.

Al-Qaeda in the Arabian Peninsula (AQAP) is a sworn enemy of the Shi'ite Houthi rebels that seized Sanaa earlier this year.