Indonesia has arrested three suspects in connection with a series of terror attacks that killed at least seven people and injured 20 others in the capital Jakarta.
Three men were arrested at their homes in the Depok area on the outskirts of Jakarta early Friday morning, police told Indonesian Metro TV news channel.
Police chief Colonel Dwiyono said the suspects are being questioned over possible links to the Thursday attacks.
Meanwhile, an alert has been imposed throughout Indonesia, national police spokesman Anton Charliyan said Friday as army trucks thundered through the capital.
Charliyan said police would be conducting raids in the day as they probe those responsible for the bloodshed.
The assault left five attackers, a Canadian and an Indonesian man dead and 20 others injured, according to police.
The attackers detonated explosives and shot at people in a district packed with malls, embassies and UN offices and waged gunbattles with police.
According to Jakarta Police Chief Tito Karnavian, the assailants had links with the Daesh Takfiri terrorists and were part of a group led by Bahrun Naim, an Indonesian militant whom police say is currently based in Syria.
"We have been informed by our intelligence that an individual named Bahrun Naim, based on the communications ... instructed his cells in Indonesia to mount an attack in Indonesia," said Karnavian.
According to him, Naim was once arrested in Indonesia in 2010 for illegal possession of ammunition and was sentenced to at least two years and a half in prison. He later left Indonesia and is now in the Daesh-held northern Syrian city of Raqqa, from where he had sent money back home to finance the attack.
The Daesh Takfiri group has claimed responsibility for the attack in an official statement posted online.
The attack followed several warnings in recent weeks by police that Daesh militants were planning something big.
It was the first major attack in Indonesia's capital since the 2009 bombings of two hotels that killed seven people and injured more than 50.
Before that, bombings at nightclubs on the resort island of Bali in 2002 killed 202 people, mostly foreigners.