Mauritania president wounded after 'accidental' shooting
They did not give further details and it was not immediately clear why the military convoy opened fire on the convoy.
"On his way back to Nouakchott, the presidential convoy was shot by a Mauritanian patrol ... as they did not recognize his convoy," Communications Minister Hamdi Ould Mahjoub said on national television.
"The president was shot on that occasion, but he is lightly wounded and his life is not threatened," he said.
Security forces blocked roads leading to the military hospital, but security did not appear to be heightened around the presidential palace or other official buildings, according to a Reuters witness.
Mauritania launched numerous military operations on Islamist bases in neighbouring Mali before a rebellion in that country split it in two, placing its vast desert in the hands of heavily-armed groups linked to al-Qaeda.
Mauritania, which straddles black and Arab Africa on the West coast of the continent, has enjoyed several years of relative political stability.
Abdel Aziz has faced some protests over complaints ranging from corruption to his poor handling of a recent food crisis.