Sana’a, Asharq Al-Awsat—Most of the prisoners freed from Yemen’s national security headquarters in Sana’a by Houthi rebels on Wednesday were Iranian military personnel and members of Lebanese Hezbollah, a Yemeni intelligence source told Asharq Al-Awsat, as clashes reignited in the capital early on Saturday between the Houthis and government forces.

The source, who requested anonymity because he was not authorized to brief the media, added that many of the freed were “high-ranking” officers or “military trainers,” with some also “involved in smuggling arms into Yemen.”

The source said they were still in the country, particularly the Houthi strongholds of Saada and Amran.

The Shi’ite Houthi group overran the headquarters of the country’s intelligence service in central Sana’a on Wednesday, setting free a number of prisoners including the crew of an Iranian ship captured off the Yemeni coast in January 2013, which was allegedly being used to smuggle a large cache of weapons to Houthi militants.

A number of members of Iran’s Islamic Revolutionary Guard Corps were also reportedly among those set free.

Meanwhile, eyewitnesses reported that clashes broke out between armed Houthi rebels and government forces after the rebels attempted to raid the home of Ali Mohsin Al-Ahmar, the head of the country’s intelligence service, near the presidential palace early on Saturday.

The eyewitnesses said they had seen several dead and injured following the attacks by the rebels, which were blocked by the security forces guarding Ahmar’s home, and that both sides were continually receiving reinforcements, with the government side boosted by the arrival of members of the Yemeni Presidential Guard.

The Houthis, meanwhile, accused the security forces stationed outside Ahmar’s home of firing first, killing three and injuring eight of the group’s members during the clashes.

The Shi’ite group have been in control of large sections of the capital since last Saturday, following a month-long series of large protests staged by the group across Sana’a to demand the formation of a new government and the reinstatement of fuel subsidies.

A UN-brokered ceasefire was signed between the government and the Houthis last Sunday which stipulated an end to hostilities and the protests, the appointment of a new government, the reinstatement of subsidies, and the appointment of members of the Houthi-affiliate Ansar Allah to act as advisers to President Abd Rabbuh Mansur Hadi, together with some members of the pro-secessionist movement Al-Hirak.

However, clashes have continued despite the agreement, with the Houthis laying siege to several government buildings including the intelligence headquarters.

Meanwhile, eyewitnesses told Asharq Al-Awsat that unknown assailants fired rockets on the US embassy building in the capital on Saturday.

The eyewitnesses said the Houthis then took control of the security checkpoint next to the embassy and the Sheraton Hotel, which staff and security personnel from the embassy have been using as a base since a rocket attack by the Al-Qaeda-affiliate Ansar Al-Shari’a on the embassy in 2012.

Although Ansar Al-Shari’a claimed responsibility for the attack on Saturday, saying it was retaliating against an American drone attack in the northern Al-Jawf province on Friday, an embassy spokesman cast doubt on the group’s claim.

The spokesman told Asharq Al-Awsat there was “no reason to believe the attack was intended for the embassy,” adding that the Yemeni government was now looking into the matter.

One security source, who requested anonymity because he was not authorized to brief the media, told Asharq Al-Awsat two rockets had hit the embassy building, and that there had been no casualties or injuries. The source said the security services were now investigating the attack.

Meanwhile, a Houthi spokesman said on Saturday that the movement had signed an addendum to the ceasefire agreement signed last Sunday, stipulating the end of fighting in Sana’a, Amran, Al-Jawf and Ma’rab, the withdrawal of all Houthi fighters from these areas, the redeployment of government forces to their posts, and the return of weapons seized from military and security installations and personnel.

The movements’ refusal to sign the agreement last week had fueled fears of continued large-scale clashes between the Houthis and the Yemeni government, and even outright civil war.