The package bombs that exploded on March 12 have been connected to a third incident on March 2 that led to the death of a 39-year-old man.
At a press conference Sunday, the Austin Police Department, along with FBI and ATF agents, pleaded for tips that could help them solve these cases.
TIMELINE: Austin's deadly package explosions
Authorities said the reward for information will rise from $65,000 to $115,000, which includes a $15,000 reward from Gov. Greg Abbott's office.
Investigators said in the last week, they have received 735 suspicious package calls, 435 leads and interviewed 236 people who have come forward with information.
Anthony House, 39, died from his injuries in a package bombing at his home on March 2.
On March 12, 17-year-old Draylen Mason was killed when he and his mother opened a package found outside their home. His mother was left injured in the attack.
Later that day across town, a 75-year-old woman was injured when she also found a strange package on her porch.
Anyone with information regarding the package bombing investigation is urged to contact the Austin Police Department at 512-472-TIPS.
Teen killed, 2 women injured by package bombs in Austin
Police: 2 deadly package bombs in Texas capital are linked