Screenshot via TV One
Reuters India cited a police spokesman who said three police officers and three civilians are among the dead. The news agency also reported that security forces were seen entering the Starbucks that was targeted.
Local media reported that at least six bombs may have gone off, according to a report from Reuters.
One of the blasts reportedly occured inside a Starbucks. "The Starbucks cafe windows are blown out," a Reuters photographer reported, " I see three dead people on the road. There has been a lull in the shooting but someone is on the roof of the building and police are aiming their guns at him."
REUTERS/Darren Whiteside
According to the official Jakarta police Twitter account one explosion went off in front of the Sarinah mall, on a main city avenue. Media said a police post outside the mall was blown up.
"I saw a police officer shot right in front of me," one witness told TV One.
Police snipers were deployed, according to media.
A UN building near the scene was in lockdown with no one allowed in or out, a witness said. Some other buildings in the area were evacuated.
Here is where the UN offices are located in the Indonesia capital:
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"We have previously received a threat from Islamic State that Indonesia will be the spotlight," police spokesman Anton Charliyan told reporters. But he said police did not know who was resposible.
Indonesia's central bank is located in the same area, and a spokesman for the bank said a policy meeting was going ahead and a decision on interest rates would be announced as planned later in the day.
An explosion was heard in the western suburb of Palmerah, according to a domestic media tweet, but police said they could not confirm a blast there.
Indonesia has the world's largest Muslim population, the vast majority of whom practise a moderate form of the religion.
REUTERS/Beawiharta
Police have been largely successful in destroying domestic militant cells since then, but officials have more recently been worrying about a resurgence inspired by groups such as Islamic State and Indonesians who return after fighting with the group.
The last major militant attacks in Jakarta were in July 2009, with bombs at the JW Marriott and Ritz Carlton hotels.
(Reuters reporting by Jakarta Bureau; Reuters editing by Robert Birsel and Simon Cameron-Moore)