Foiling the unidentified attackers on Sunday, Nabil Sadiq al-Basha’s bodyguards fought off the ambush 190km south of the capital, Sanaa.
A member of parliament from Yemen's ruling General People's Congress (GPC), al-Basha was uninjured.
In a separate development, the assassin of Jar Allah Umar, the late assistance secretary general to Yemen’s National Authority (NA), has been sentenced to death.
But the NA criticised the court verdict on Saturday, claiming a shallow investigation failed to identify motives, accomplices and evidence publicly.
Dr Abd al-Qudus al-Midhwahi, a member of the NA, said all hope of discovering the truth would accompany Ali Ahmad Jar Allah to his grave and suggested a government cover up or possible involvement.
Muhammad Kahtan of the Islah party even called on the Yemeni authorities to stop using armed force against political opponents, claiming the judiciary were not independent.
Dealing with violence
Violence is common in Yemen, a country with a tribal structure where the number of firearms held by civilians is officially estimated at more than 60 million, an average of more than three for each inhabitant.
In an attempt to deal with armed Islamist movements, Religious Endownments Minister Yahya al-Najjar said many imams around Yemen were being replaced with foreign Muslim preachers.
"We already have 13 Arab preachers and we will hire another 23 as part of reforms aimed at ridding dozens of mosques of the influence of religious groups and parties that use them to incite extremism," he said.