Australian security officials reportedly carried out a check on Man Haron Monis days before he took hostages at a cafe in Sydney, after a tip-off from a member of the public.
News Corp Australia has reported an anonymous caller rang the national security hotline warning of the extremism of Monis and saying officials should look at his website.
It said the Australian Security Intelligence Organisation (ASIO) checked Monis' website as a result of the phone call.
The ASIO found he had a number of websites and a Twitter account in support of Islam and jihadism but there was no mention of a planned terrorist attack.
Monis took 17 people hostage at the Lindt Chocolate Cafe in Martin Place last Monday. The siege ended early on Tuesday with three people killed, including Monis.