Shots were fired at the convoy of Yemen's Prime Minister Khaled Bahah as the country was plunged into chaos following an attack by Shi'ite Houthi rebels on the capital.
It was not immediately clear if Bahah was wounded in the attack that came as he was leaving the presidential palace for a meeting with rebel representatives.
Information Minister Nadia Sakkaf earlier said that a ceasefire deal had been reached and talks were to be held.
Gun battles were nevertheless reported across Sanaa. Houthi fighters took over the headquarters of Yemeni state television and the official SABA news agency, prompting Sakkaf to cry that the situation was spiralling towards a coup.
"This is a step toward a coup and it is targeting the state's legitimacy," the minister said.
Gunfire and explosions were also heard near the residence of President Abed Rabbo Mansour Hadi.
Houthi rebels overran Sanaa in September and their fighters have been patrolling its streets ever.
The rebels and the Yemeni military traded blame for initiating today's violence (19 January).
The Houthis' al-Maseera satellite television claimed that the army fired on a Houthi militia patrol near the presidential palace without reason. In turn the army said they were provoked into opening fire.
Both parties also accused each other of not implementing a UN-brokered peace deal agreed in September.
The Houthis have been staging periodic anti-government revolts since 2004, with critics saying they are trying to destabilise the central government to create a semi-independent state in their northern heartland, the Saada province.
Deposed President Ali Abdullah Saleh has been accused of orchestrating the last uprising and has been put on a UN sanction list for destabilising the country - an allegation he denies.
Saleh and the Houthis adhere to a branch of Shia Islam known as Zaidism.