Yemeni protesters kept up the heat on President Ali Abdullah Saleh on Saturday as fresh clashes raged in the flashpoint city of Taiz, and as a dissident general denied aiming to replace the Yemeni leader.

Yemen recalled its ambassador to Qatar, state news agency Saba announced, after a call from the Gulf state for Saleh to step down stirred anger in his regime.

The army shelled a suspected Al-Qaeda refuge in southern Yemen on Saturday, after the US expressed concern that pressure on the group had eased amid months of protests calling for the president’s departure.

An officer from Yemen’s 25th mechanised brigade said army units had begun shelling the Joar area in Abyan province.

The attack came two days after US Defence Secretary Robert Gates said Yemen had, since the outbreak of its political crisis, ‘really eased up the pressure on Al-Qaeda in the Arabian Peninsula,’ referring to the group’s local affiliate.

Police fired volleys of live rounds at demonstrators in Taiz on Saturday, in what local residents termed some of the worst violence since anti-regime protests broke out in Yemen in January.

At least 14 people were shot and wounded, three of them seriously, and hundreds more needed treatment for tear-gas inhalation, medics said.

Witnesses said security forces attacked protesters, angry at the killings of four demonstrators over the previous 24 hours, gathered near the government offices of the city, south of the capital, Sanaa.

On Saturday night, seven protesters were wounded by police and another 150 treated for tear-gas inhalation after thousands of them left their base in the university square and marched on a police control point, witnesses said.

Three of the wounded were hit by live bullets and the others beaten by regime supporters, they added.

Earlier on Saturday, thousands of protesters massed in Al-Hurriya (Liberty) Square in Taiz, calling for those behind the deadly shooting of protesters to be held to account and for Saleh to go.

Medics said Yemeni security forces shot dead four protesters and wounded 116 in the flashpoint city in clashes that erupted on Friday and carried on into the next morning.

Clashes lasted until about 3.00am local time on Saturday, with protesters trying to take over a provincial government building near the square, witnesses said.

In another bastion of opposition to Saleh, a protest strike paralysed southern Yemen’s main city of Aden, where shops were shuttered in many districts, roads were cut off and public transport ground to a halt.

Six hours later, the protesters reopened shops and roads but vowed to continue with similar daytime strikes every Saturday and Wednesday.

Meanwhile, General Ali Mohsen al-Ahmar, who has sided with anti-regime demonstrators and accused regime supporters of trying to kill him, denied having his sights set on political power.

Ahmar, who commands Yemen’s northwest military district including Sanaa, pledged in late March to defend the protesters, who have pressed since January for Saleh’s departure.

Ahmar told an envoy of UN chief Ban Ki-moon that ‘the army will be under the control of civilians, and I do not seek any position of power’, according to an overnight statement from the general’s office.

Yemen’s foreign ministry said Sanaa’s ambassador to Doha was ‘recalled for consultations following remarks by (Qatari Prime Minister) Sheikh Hamad bin Jassim bin Jabr al-Thani.’

Sheikh Hamad said on Thursday that Yemen’s Arab neighbours in the Gulf ‘hope to reach a deal with the Yemeni president to step down,’ a position which Saleh slammed as a case of ‘blatant interference in Yemeni affairs’.

The United States, which has cooperated closely with Saleh in its battle against Al-Qaeda, on Friday urged all sides in Yemen to engage in an ‘urgently needed dialogue’ on a political transition.

Washington has expressed concern that Al-Qaeda militants could take advantage of unrest in Yemen, and that pressure from the impoverished country on the group has let up.

l Courts in Tunisia are handling nearly 200 cases of killings by snipers committed during the uprising that toppled the president on January 14, the official TAP agency has reported.

‘The courts have taken up 192 cases of killings of Tunisians by snipers during the events of the revolution,’ TAP reported.

Several members of the security forces had been arrested, warrants had been issued against others and work was continuing to identify other suspects, the agency added.

Tunisia’s transitional government has on several occasions denounced a plot by supporters of the former president Zine el-Abidine Ben Ali to provoke chaos in the country.

The country was shaken by bloody clashes in several regions during the uprising, with 25 demonstrators killed by snipers in the town of Kasserine alone, according to hospital sources.

l Arab unrest is shaking the foundations of US counter-terror efforts that have long relied on spy agencies under authoritarian regimes to help fight Islamist militants.

With popular protests toppling rulers in Tunisia and Egypt and threatening leaders in Yemen and elsewhere, US intelligence agencies are struggling to adjust to a radically changed landscape, US officials, former intelligence officers and experts say.

The US for years has counted on Arab allies to back up its diplomatic and security interests, enlisting their help to combat Al-Qaeda with harsh tactics and interrogations.

But the political wildfire spreading across the region means US spy services will have to deal with new intelligence chiefs more wary of Washington and more reluctant to cooperate on covert projects that might be unpopular with their citizens.

‘The immediate effect, there’s no question, is that a lot of relationships which we have built over the years to fight Al-Qaeda and like-minded terrorists are over,’ said Bruce Riedel, a former CIA officer.

Key figures who became trusted partners for US intelligence services such as Omar Suleiman, Egypt’s former spy chief, are now gone and their successors will likely be less willing to do Washington’s bidding, said Riedel, a fellow at the Brookings Institution.

US officials are most alarmed at the fallout from upheaval in Yemen.

‘The focus of Yemeni intelligence is not on Al-Qaeda anymore, it’s on surviving and figuring out who’s going to be the next boss,’ Riedel said.

Anxious to see an end to protracted unrest, President Obama’s administration has dropped its support for Saleh, urging him to peacefully hand over power.

Even if some semblance of stability is restored in Yemen, Al-Qaeda will have emerged stronger, raising the threat of another attack on Western targets by the network’s affiliate there, Riedel warned.

The political earthquake in the Middle East will likely mark the end of an era for US power in the region and curtail the reach of US intelligence agencies, said Michael Desch, co-director of the University of Notre Dame’s international security programme.

‘Part of the reality of the new world that we’re moving in to is we’ve got to recognise the limits of our influence,’ Desch said.