DUBAI, Jan 14: A little-known group said on Friday it was behind the killing of an aide to Ayatollah Ali al-Sistani, Iraq's top Shia scholar and a main driving force behind the Jan 30 elections, according to an Internet message.

"With the help of God, a detachment from Ansar al-Islam Group was successful in killing Mahmoud Madaen - an aide to the polytheist Sistani - who was a leading supporter of the elections," said the message, posted on Islamist Web sites. Religious scholar Madaen was killed on Wednesday in a town south of Baghdad, along with his son and four guards.

The message was signed by Ansar al-Islam Group - Saad bin Abi Waqqas Brigade. It was not immediately clear if the group was linked to Ansar al-Islam, a militant Islamist organization with alleged Al Qaeda ties which operated in northern Iraq before US-led forces invaded the country in 2003.

"This is the first but not the last strike of the Ansar al-Islam Group, as we will go after all mercenaries and traitors who have sold their honour," said the statement, which could not be authenticated. -Reuters