A convicted Islamic extremist in Indonesia running a popular jihadi website has been profiting from revenue generated by online advertising platforms according to reports..

Muhammad Jibril Abdul Rahman, whose website Arrahmah.com featuring pictures of beheadings has garnered 600,000, and on occasion upwards of 1 million visitors, a month, has been using platforms such as Google’s Adsense to feature advertisements from companies such as Microsoft, IBM and Citigroup, according to Britain’s Financial Times.

Jibril, also dubbed the ‘Prince of Jihad,’ was sentenced to five years in prison for his role in the 2009 bombing of Jakarta’s JW Marriott and Ritz-Carlton hotels that left seven people dead.

Jibril was accused of knowing about the plot, aiding the bombers and forging documents.

A member of Southeast Asian terror group Jemaah Islamiyh that has links to Al Qaeda, Jibril was one of three people sanctioned by the U.S. Treasury Dept. in 2011 with the department stating “U.S. persons are prohibited from engaging in transactions with these individuals. and assets they may hold under U.S. jurisdiction are frozen.”

Google said Arrahmah.com’s account has been terminated, although the site is still connected to the $160 billion global online ad market through third-parties who are still placing advertisements on the site.

“We take the quality of our network very seriously and invest significant time and resources to keeping bad actors out of our system. We also have strict policies and terms of use which govern the type of publishers we allow on AdSense,” Google said.

“We have a number of policies and procedures in place for our vendors designed to help prevent our advertising from appearing on inappropriate sites,” Citigroup said in a statement about its ads appearing on the site.

“In this case, we have acted quickly to rectify the issue and have taken steps to ensure our ads will not appear on this site in the future.” Citigroup added.

Rahman is “the most important online terrorist in Southeast Asia,” according to Rohan Gunaratna, head of the International Center for Political Violence and Terrorism Research at Nanyang Technological University in Singapore.

“The purpose of his site is to polarize and radicalize people so that they become ripe for recruitment,” Gunaratna said.

Funding a U.S. designated terrorist organization is a criminal offense punishable by 20 years in prison or a $1 million fine, but the highly automated nature of online ad placement may suggest Google unknowingly funded the propaganda site.