SANAA (Reuters) - At least 33 people were killed in a suicide bombing and gun attacks in central Yemen, tribal sources and medics said on Monday, as al Qaeda fighters seized a Yemeni city in a new challenge to the central government.
Violence has spread in Yemen since Shi'ite Muslim Houthis took over the capital, Sanaa, last month, threatening the stability of a country that borders on Saudi Arabia, the world's biggest oil exporter.
Houthi forces have fanned out into central and western Yemen, posing a challenge to Sunni tribesmen and al Qaeda militants, who regard the Houthis as heretics. Fighting has flared in several provinces.
In the latest attacks, an al Qaeda suicide bomber drove a car towards the home of a local government official in the town of Radda in al-Bayda province, killing at least 13 people, medical sources said.
Ansar al-Sahrai, an al Qaeda affiliate, said in a statement the attack targeted a meeting at a Houthi leader's house and that "dozens were killed or wounded".
Earlier in the day, tribal sources said al-Sharia fighters on Sunday night shelled a Radda house where a local Houthi leader lives, killing gunmen.
At least 10 Houthi fighters were killed in two other incidents, one on the outskirts of Radda and another at a checkpoint in the nearby Ibb province, tribal sources said.
Ansar al-Sharia said in a report from the al-Orsh area in al-Bayda that "dozens of Houthis" have been killed or wounded in battles since Sunday evening, and that two of its fighters were killed in Ibb.
Radda, with a population of 60,000, has long been a stronghold of Ansar, which includes many fighters from local tribes who are up in arms over the presence of Houthi rebels in the mainly Sunni region.
There is growing international concern about Yemen's turmoil because of its proximity to Saudi Arabia and international shipping lanes, as well as the risk of al Qaeda using the country as a springboard for attacks abroad.
In a significant development, residents and activists said al Qaeda fighters had marched into al-Odayn, a city of 200,000 in the central province of Ibb, captured the local government offices and raised their black and white flag over it.
"They came in at midday, invaded the town, chanting Allahu Akbar (God is Greater) and seized the government compound unopposed," one resident of al-Odayn said.
Residents also said Sunni militants destroyed the home of a local Houthi member who had been trying to recruit local fighters to join a popular committee, a kind of a grassroots police force Houthis have established in other parts of the Arabian Peninsula country.
The Houthis' advance and clashes with Ansar al-Sharia prompted often faction-ridden regional Sunni tribesmen to close ranks to try to protect themselves.
In a statement issued on Sunday, a committee of local tribesmen warned that they would not tolerate the presence of "any armed militia from any party" in al-Bayda province and called on the central government to step in to maintain order.
"The state must carry out its national duty to spare the province of sectarian strife," said the statement, which was obtained by Reuters.
The Yemeni armed forces have largely avoided confronting the Houthis since they moved into Sanaa last month, leading to speculation that President Abd-Rabbu Mansour Hadi was tacitly allowing the group to move freely while a new government is being formed.
Whether it would command more authority than the last one is questionable, however. While the Houthis signed a power-sharing pact with other political parties, that has not deterred them from thrusting into other regions of Yemen.
In a further sign of gathering chaos, al Qaeda militants on Monday raided the Um al-Maghareb military airport in the eastern province of Hadramout province, not far from the Saudi border, and looted equipment, military and security sources said.
Reporting by Mohammed Ghobari; Writing by Sami Aboudi; Editing by Mark Heinrich, Larry King