A federal official told The Associated Press late Tuesday that the explosion is believed to have been intentional and may have come from a package.
An explosion at a California medical building on Tuesday - which left one person dead and three others injured - was the result of "an intentional detonation", according to FBI investigators. No children were hurt, officials said.
But police have not confirmed this and they say no device was found.
Bomb squad investigators and FBI agents were looking into the cause of the blast Tuesday.
Associated Press writer Michael Balsamo in Los Angeles contributed to this report.
JD(S) chief HD Kumaraswamy, son fly off to Singapore
For the Janata Dal (Secular), or JDS, a favourable verdict would establish its stature as a regional kingmaker. He took to Twitter to urge Congress workers to take rest and assured them of a victory with a clear majority.
A daycare and preschool are near the site of the explosion, but authorities said all of the children are safe.
Orange County sheriff's experts along with FBI, the ATF and other federal agencies are investigating the cause of the blast. Dave Sawyer said Tuesday night that the size of the explosion makes it suspicious.
Tony Bommarito of the Orange County Fire Authority said, according to NBC News.
A witness describes seeing two women with burns following an explosion that killed one person and injured three at a Southern California medical office building.
A woman who was on her way to an appointment in the area told CBS2 she arrived just after the blast occurred, and she saw fire on the roof of the building. The condition of the injured were not immediately known.
Nothing indicates there were any threats made before the blast, which appeared to be concentrated in a suite on the first floor of the office building, Sawyer said.
Officials haven't released information about the person who was killed. Authorities say one person is dead and several others have injuries.
"... They weren't on fire, they were helping each other across the street, walking very slowly and a lot of shock, shaking, just full of ash all over their face, eyes bloodshot, just blood all over", the woman said.
Chief Fennesy noted the building where the explosion occurred was being renovated.
Although the cause of the blast was still unknown, Bommarito told reporters around 3:30 p.m. that there was "no immediate hazard" to the community. The injured were taken to a hospital.
North Korea To Shut Down Nuclear Site Publicly
They said that after six tests, all conducted in deep tunnels, the place has caved in and become too unstable for another test. Saturday's announcement came ahead of a scheduled summit between Kim and U.S.
Children at a day care across the street from the building were evacuated.
China, for its part, has stated that it is willing to buy more American goods and services to help reduce the trade deficit. ZTE should not be operating in the United States and should not have easy access to American technology , Rubio said.
People began getting sick last November and illnesses that occurred after March 23 might not yet be reported, the CDC said. For a full list of recalled brands, consumers are urged to check the Food and Drug Administration's website .
City are due to celebrate their title success with an open-top bus parade through the streets of Manchester today. Swansea needed a 10-goal swing - beating Stoke and seeing Southampton hammered by Manchester City - to stay up.
Both these resolutions affirm that Jerusalem would be the capital of the future Palestinian State and the State of Israel. Since March 30, Palestinians have been holding the so-called Great March of Return, near the border of the Gaza Strip.
The shirt could not be found on Gap websites and it wasn't clear whether it was still being sold in shops in some countries. China has been ramping-up efforts to police language used to describe Chinese-claimed territories such as Taiwan .
The Racing back-up took the place of Dan Carter - the victim of a hamstring injury - on the bench just before kick-off . But Sexton responded with a penalty and Iribaren's fourth penalty was cancelled out by Nacewa's boot.
Supporters of Hussein flocked to the Criminal Court in Omdurman, Sudan's second-largest city, in protest during the trial. According to BuzzFeed News , Noura was forced to marry Abdulrahman Mohamed Hammad by her father when she was 16.
There's good and bad news for fans of Gotham
In the meantime, we get to keep guessing and asking questions because at least we know Gotham is coming back for another season. Sources tell The Hollywood Reporter that the pickup is for 13 episodes, though the network and producers Warner Bros.
Terrorist attacks in Indonesia
Also on Sunday, police said they killed four suspected members of JAD in Cianjur, in West Java province, and arrested two others. Tito Karnavian, Indonesia's highest-ranking police official, told reporters seven victims were killed.