ADEN, Yemen (CBS News/CBSDC/AP) — The U.N.’s special envoy for Yemen, Jamal Benomar, warned an emergency meeting of the U.N. Security Council on Sunday that events were pushing the country “to the edge of civil war.”

Benomar, appearing in a video briefing from Qatar, said “it would be an illusion” to think the rebel Houthis in control of the capital could take control of the entire country, and he urged all parties to resolve the conflict peacefully.

After hearing from Benomar, the Security Council approved a strong, but unenforceable presidential statement which supports Yemen’s embattled president, pleads with all factions to negotiate, and warns terrorists involved in recent bombings that they will be brought to justice, reports CBS News’ Pamela Falk.

The warning of civil war came as Yemen’s Shiite rebel leader escalated his attack Sunday against the country’s embattled president, vowing to send fighters to the south where Abed-Rabbo Mansour Hadi has taken refuge. The fiery speech came hours after his militia seized the third- largest city of Taiz, an important station in its advance.

Abdel-Malik al-Houthi, who is backed by supporters of former President Ali Abdullah Saleh, said the mobilization is aimed at fighting al Qaeda and other militant groups, as well as forces loyal to Hadi who are in the south intending to further destabilize Yemen.

In his one-hour speech on al-Masirah TV, al-Houthi called Hadi a “puppet” to international and regional powers who want to “import the Libyan model” to Yemen. He named the United States, Israel, Saudi Arabia and Qatar as conspirators against Yemen and other countries in the region.

Libya is torn by warring militias with rival parliaments on either end of the country claiming legitimacy and radicals from the Islamic State group taking root.

Yemen’s turmoil has deepened since the Shiite rebel group, known as the Houthis, seized Sanaa in September, putting Hadi under house arrest and eventually dissolving the country’s parliament. They now control at least nine of the country’s 21 provinces.

Hadi, who is backed by the international community, fled to Aden – the country’s second most important city and economic hub – declaring it a de-facto capital earlier this month.

The escalation Sunday began when forces loyal to Saleh took over Taiz and its international airport. Security officials allied with Hadi said the rebel forces were already mobilizing tanks and fighters on the road from Taiz to neighboring Lahj province, apparently on their way to Aden.

“The decision (to mobilize) aims to confront the criminal forces, al Qaeda, and its partners and sisters, and all those who want to take cover in regions or using political pretexts,” al-Houthi said. He accused Hadi of partnering with militant groups to destabilize Yemen.

Security officials said one person was killed and four wounded when rebel fighters opened fire on protesting crowds in Taiz against their advance in the city, which was known as a hotbed for protests against Saleh in the beginning of 2011 that forced him to step down.

The security officials spoke on condition of anonymity because they were not authorized to brief the press.

If the rebels hold onto Taiz, the capital of Yemen’s most populous province, it would pose a major threat to Hadi in Aden, just 85 miles away.

The turmoil has undermined Yemen’s ability to combat al Qaeda in the Arabian Peninsula, the target of a U.S. drone program, and the country now also faces a purported affiliate of the extremist Islamic State of Iraq and Syria group, which claimed responsibility for a series of suicide bombings killing at least 137 people Friday.

A day earlier, U.S. troops evacuated a southern air base crucial to the drone program after al-Qaida militants seized a nearby city.

All these factors could push the Arab world’s most impoverished country, united only in the 1990s, back toward civil war.

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