At least 14 people were killed and 17 were injured after three people opened fire at a social service agency’s holiday party in San Bernadino, California, on Wednesday. In the manhunt and police gunfight that followed, a man and a woman were killed on a residential street, the Wall Street Journal reported.

The man was identified as Syed Farook, a 28-year-old US national, the country's media reported. His family expressed shock at the arrest, and said they did not know what his motive could be. The woman was identified as 27-year-old Tashfeen Malik, and is thought to have been married to Farook. Farook was an employee at the Inland Regional Center's environmental health team. He left the Centre in the morning following a dispute at the Christmas party being held there, but later returned to open fire, The Guardian reported. A third person was detained, though it is unclear whether they were involved in the shooting.

According to the police, the attackers came prepared for the shooting with combat-style clothing and long guns. They ran away after the carnage, but the police tracked them down to a black SUV in a residential area some miles away, the BBC reported. Residents have been told to stay inside their homes till it is confirmed that the third suspect has been caught. County and city buildings, schools and hospitals have been put in lockdown.

This was the deadliest incident of gun violence in the United States in three years, and drew a strong reaction from President Barack Obama, who has been trying to champion gun reform laws throughout his tenure. "We should never think that this is just something that just happens in the ordinary course of events, because it doesn't happen with the same frequency in other countries," Obama said, according to CNN. American Muslim leaders condemned the act and said they stood in solidarity with the families of those killed and wounded.