There were also two victims who survived the attacks: One is a 75-year-old woman who remains in critical condition and the other is a woman in her 40s.
Authorities were investigating the bombings as a possible hate crime.
"[We're] not ruling hate out at this time," he said.
Meanwhile, Manley said the reward for information leading to the suspect or suspects had been increased to $100,000.
That's in addition to Gov. Greg Abbott's $15,000 reward.
Since the explosions occurred, Manley said the Austin Police Department has received help from an estimated 500 federal agents from various departments, 735 suspicious packages had been reported, 236 interviews have been logged, and 435 leads have been checked out.
Manley emphasized that he wants more tips to come in and that to solve this case it will take "the public's assistance."
And no tip or potential clue is too small or inconsequential, he added.
"You may have the one piece of information that puts us ahead," said Manley.
He also said law enforcement has a better understanding of the "construction of these bombs and their components" after the material evidence had been analyzed in a laboratory overseen by the Bureau of Alcohol, Tobacco, Firearms and Explosives.
Kaynak:Abcnews