Updated 10:20

The Texas serial bombing suspect is dead according to US police.

Austin Police chief Brian Manley confirmed the death of the man, who has not been named, after officers tracked him down to a hotel in Round Rock, near Austin.

The suspect has only been identified as 24-year-old white male.

Police said he set off the explosive device inside his vehicle as a SWAT team approached.

One of the SWAT officers also shot at the vehicle and an officer was injured in the explosion.

Mr Manley said the the motive behind the series of bombing to hit the US state, which killed two people, was unknown.

Police traced the man using a mix of cell phone technology, CCTV footage of one of the previous attacks and store receipts.

The suspect was identified in the last 24 hours after shipping an explosive device from a FedEx store in the Texas capital, the Austin Statesman said.

A FedEx worker was injured after the package containing nails and shrapnel exploded.

Authorities found store receipts showing suspicious transactions and obtained a search warrant for his Google search history which also showed suspicious behaviour, an official told the newspaper.

Police then used mobile phone technology to trace the suspect to a hotel in Williamson County and a chase ensued, according to reports.

The string of bombings in Austin over the past two weeks have killed two men so far – Anthony Stephan House, 39, and Draylen Mason, 17.

Four others have been injured.

US president Donald Trump branded the person behind the attacks a "very sick individual."