One of Yemen's top journalists and activists close to the country's dominant Houthi militia, Abdul Kareem al-Khaiwani, has been killed, the group's official television channel al-Maseerah said.

The son al-Khewani, who is also a respected writer, said a pair of armed men riding on a motorbike opened fire and gunned down his father as he came out of his home on Wednesday morning.

Mohammed al-Khewani said the attackers left his father in a pool of blood and sped away. The elder al-Khewani was transferred to hospital but died of his wounds there.

Yemen is deeply polarised and engulfed in turmoil amid a power grab by the rebels known as the Houthis who last year seized Sanaa and several northern provinces.