REFILE-Sunni, Shi'ite Islamists clash in Yemen, one killed

(Fixes to say "west of Amran" in para 8)

SANAA, Sept 21 (Reuters) - Clashes between Shi'ite and Sunni Islamist groups in Yemen killed one person on Friday, the latest violence between groups vying for influence in the Arabian Peninsula country after the ouster of veteran president Ali Abdullah Saleh.

Al Qaeda and other Islamist groups gained strength in Yemen during the chaos of the uprising and have engaged in intermittent clashes over the past year.

The Sahwa website run by the Sunni Islah party said a preacher died in an attack by followers of the Zaydi Shi'ite group known as the Houthis on a mosque in a district of Amran province north of Sanaa.

A Defence Ministry statement said one person died in clashes between armed men.

Islah, which has taken the lion's share of posts given to opposition parties in the post-Saleh government, includes many puritanical Islamists known as Salafis with close links to Saudi Arabia.

The Houthis have complained of marginalisation in the transition. They have a strong presence in northern provinces, where they have fought several wars with central government forces since 2004 and fought Saudi forces in 2009.

Saleh's government accused Shi'ite power Iran of backing the Houthis with money and weapons.

The Houthis, who call themselves Ansarallah (Partisans of God), said two of their men died in attack by armed men from Islah in Hajjah province west of Amran. That report was not immediately verified by government sources.

The Houthis, who observers say model themselves on Lebanon's Hezbollah, have tried to assert their strength in Sanaa, where they have many followers among Zaydi Shi'ites.

In recent weeks they have put up anti-U.S. banners in Sanaa and drawn anti-U.S. graffiti, casting themselves as the leading force against U.S. policy in Yemen.

(Reporting by Andrew Hammond, editing by Diana Abdallah)