A car bombing claimed by the Islamic State group near a mosque in Yemen's rebel-held capital killed four people Wednesday, medical sources and witnesses said.

An IS Twitter user calling himself Karar al-Moayad said the jihadist group had carried out the attack and that it had caused "several dead".

A car bombing claimed by the Islamic State group killed four people near a Shiite mosque in the rebel-controlled Yemeni capital Sanaa, the Shiite rebels said.

Children were among eight people wounded in the Monday evening blast, the rebel-controlled Saba news agency said.

Yemeni ministers have arrived back in Aden from Saudi exile after the government announced the "liberation" of the country's second city from Iran-backed rebels, the interior minister said on Saturday. 

"We arrived last night," Abdo al-Huzeifi told AFP, adding that he was accompanied by Transport Minister Badr Basalma and several security officials.

Saudi-led coalition warplanes bombarded Yemeni rebels Sunday, witnesses said, in a new blow to a U.N.-proposed truce in the impoverished country where millions are threatened with famine.

Air strikes hit the Shiite Huthi stronghold of Saada in Yemen's north, as well as other rebel positions south of the capital Sanaa and in the southern province of Lahj, residents said.

A car bomb exploded outside a Shiite mosque in the rebel-held Yemeni capital on Tuesday, killing and wounding people, witnesses said.

The bomb, at the al-Raoudh mosque in southeast Sanaa, went off as worshipers were leaving after evening prayers.

Saudi-led warplanes bombed the Sanaa headquarters of the Yemeni party headed by rebel-allied former president Ali Abdullah Saleh overnight, the party said as officials reported 46 killed in other strikes.

The attack on the offices of the General People's Congress (GPC) caused "some deaths" among employees and guards of the building in the south of the capital, party official Faeqa al-Sayed said.

A Saudi-led air strike on a Huthi Shiite rebel stronghold in Yemen's northern mountains killed 23 people early on Saturday, tribal sources said.

The strike targeted a munitions factory in Saqayn, near Saada, the sources said.

An attack on Huthi rebel leaders in Yemen's capital claimed by the Islamic State group has killed at least 28 people, medics said Tuesday, in the latest anti-Shiite assault by the Sunni extremists.

Yemen was previously the preserve of IS' jihadist rival al-Qaida, which controls swathes of the south and east, but since March the group has claimed a string of high-profile attacks.

Fire erupted at Aden's oil refinery Saturday when rebels shelled the nearby port to prevent a Qatari ship carrying aid for Yemen's devastated second city from docking, officials told Agence France Presse.

"The rebels fired artillery rounds at the area and one hit an oil tank at the refinery, sparking a fire," said an official at the Aden Refinery Company.

Gunmen have shot dead a Huthi rebel commander in the Yemeni capital, as the insurgents came under attack elsewhere in the country, an official and tribal sources said on Friday.

The men, on a motorbike, attacked low-ranking officer Ibrahim Hassan al-Sharfi near his Sanaa home late Thursday before they fled.