Austin authorities said two men in their 20's were taken to a local hospital after another explosion was reported Sunday night. Authorities have said both men are suffering from serious, but non-life threatening injuries. According to ABC News, this incident now brings the number of explosions this month to four, in what appears to be the work of a serial bomber.

Earlier this month, two Black men died from bombs delivered as packages on their home doorsteps in Austin, Texas. 17-year-old Draylen Mason died on March 12 following the death of 29-year-old Anthony Stephan House on March 2.

Local law enforcement is offering a monetary reward in exchange for any leads regarding the horrific incidents. Buzzfeed reports Texas officials announced they will be offering $115,000 for such information on Sunday.

The package bombs also injured (but didn't kill) two others, including Mason's mother.

Along with the Federal Bureau of Investigation (FBI) and the Bureau of Alcohol, Tobacco, Firearms, and Explosives, the Austin Police Department are currently working on solving the investigation, in hopes someone from the public will approach the tip line.

Thus far, law enforcement—who believe the packages were intended to "send a message"—has received 435 leads, CNN reports. Additionally, 236 people have been interviewed regarding the crimes as well.

Texas Governor Greg Alcott contributed $15,000 to the reward fund.

Since both of the bombing victims were Black, many believe the incidents were racially motivated, especially given today's political climate throughout the state and the country.