SANAA: Triple suicide bombings killed at least 142 people Friday at Shiite mosques in the Yemeni capital, medics said, while ISIS claimed responsibility for the attacks.
In an online statement, the previously unknown Sanaa branch of ISIS warned that the bombings were "just the tip of the iceberg."
"Infidel Houthis should know that the soldiers of the Islamic State will not rest until they eradicate them... and cut off the arm of the Safavid [Iranian] plan in Yemen," the statement from the extremist group said.
One suicide bomber struck inside Badr mosque in southern Sanaa while another targeted worshippers as they fled outside, witnesses said.
The third suicide bomber targeted Al-Hashahush mosque in northern Sanaa.
The Houthi militia's Al-Massira television said hospitals in the capital had made urgent appeals for blood donations.
Leading Houthi cleric Al-Murtada bin Zayd al-Muhatwari, the imam of the Badr mosque, was among those killed, a medical source said.
Medics at three main hospitals in Sanaa told AFP they counted 142 people dead.
Footage aired by Al-Massira showed bodies lying in pools of blood outside the mosques, as worshippers rushed the wounded to hospitals in pick-up trucks.
There was no immediate claim of responsibility.
Another suicide bomber blew himself up outside a mosque in the northern Houthi stronghold of Saada, a source close to the militia said.
Only the assailant was killed in that explosion and tight security at the mosque prevented the bomber from going inside, the source added.
The Houthis overran Sanaa in September and have since tightened their grip on power.
Their attempts to extend their control into other areas have been met by deadly resistance from Sunni tribes and Al-Qaeda.
Yemen's top security body blamed Al-Qaeda for a car bomb in January that killed 40 people and wounded dozens more at a police academy in Sanaa as recruits lined up to register.
But a leader of the jihadi network denied responsibility at the time.
Al-Qaeda in the Arabian Peninsula (AQAP) is regarded by the United States as the extremist network's deadliest branch.
Yemen, a front line in the U.S. war on Al-Qaeda, has descended into chaos since the 2012 ouster of longtime strongman Ali Abdullah Saleh, who has been accused of backing the Houthis.
President Abed Rabbou Mansour Hadi escaped Houthi house arrest in Sanaa last month and fled to the southern city of Aden, where violence has erupted in recent days.
A security official said Friday that a top Yemeni officer linked to the Houthis had escaped an assassination bid near Aden overnight.
Four people were killed in an ambush on the Lahj-Taiz road but General Abdel Hafedh al-Sakkaf, the special forces chief in Aden, escaped unharmed, said the official from Lahj.
He said the attack took place in Al-Athawir as Sakkaf fled Aden in a convoy to Lahj, on its way towards militia-held Sanaa.
"He escaped the assassination bid but a bodyguard was shot dead, while three others died when their vehicle overturned," the official said.
The attack came as forces loyal to Hadi tightened their control over Aden where the situation was calm early Friday.
Troops loyal to Hadi and their allied Popular Committees paramilitary manned checkpoints, an AFP correspondent reported.
Hadi himself had to evacuate a presidential palace in Aden oThursday after a fighter jet opened fire, hitting a nearby hill.
At least seven special forces fighters and four members of the Popular Committees were killed in clashes in Aden Thursday, security sources said, and 54 were wounded on the two sides.
The violence forced the closure of the city's airport, which Sakkaf's forces tried to seize but were repelled by pro-Hadi troops and paramilitaries.
Anti-aircraft guns opened fire on planes above the presidential compound in the southern Yemeni city of Aden again Friday, according to witnesses and an aide to Hadi.
The witnesses said the planes targeted by the gunfire were flying so high as to be barely visible in the sky above the Crater district of Aden where Hadi lives.
The presidential aide confirmed that the aircraft had opened fire on the planes but gave no further details.
Following the Houthi takeover of Sanaa, Saudi Arabia and other Gulf countries moved their embassies to Aden and several Western missions closed their doors in the capital because of security concerns.