Austin police and EMS units responded to what they called a “Bomb Hotshot” call Sunday night. EMS officials tweeted confirmation of transporting two people with serious but “non-life-threatening” injuries.

Update 1:45 a.m. Monday: Chief Manley reported a “device” caused the explosion. He repeated reports that the device may have been triggered by a trip wire. Manley said this would be a departure from the previous package explosions that were triggered either by motion or by opening the package. The chief urged residents of the subdivision to remain indoors until after daybreak so that law enforcement officers could complete clearing the area.

“It is very possible that this device was a device that was activated by someone either handling, kicking, or coming in contact with a trip wire that activated the device,” Manley told reporters during a press update early Monday morning.

Update on explosion investigation with Chief Manley https://t.co/uMdIGx03Aj — Austin Police Dept (@Austin_Police) March 19, 2018

The chief confirmed that offiicals have not yet begun processing the scene of the city’s fourth bombing in less than one month. Officials are waiting for daylight so that they can properly and safely process the scene.

The chief later called the explosive device a bomb.

“We do believe, based upon what we’ve seen, that this was a bomb. that exploded. However, we are not believing that this is similar to the previous ones as in packages that were left on doorsteps,” the chief said while responding to reporter’s questions. “But instead, this was some type of a suspicious package that was left on the side of the road that detonated and injured these two men that were hurt earlier tonight.”

“We are working under the belief that they are connected,” he continued. “However, we have not processed the scene. Once we go in and do the post-blast analysis in the morning, we will have a better idea if the components of this device are similar to the other components.”

The chief said it may take lab results to confirm the connection between this bomb and the previous three package bombs.

The victims were either riding or pushing bicycles at the time of the explosion, the cheif stated as he closed the press conference.

Update 11:40 p.m.: Hospital officials report the two victims are in “Good Condition,” KVUE’s Kristie Gonzales tweeted:

JUST IN: Victims injured in tonight’s explosion in Southwest Austin are in good condition, hospital representatives confirmed to @KVUE https://t.co/Z59rTXusB9 — Kristie Gonzales (@GonzalesKristie) March 19, 2018

ORIGINAL STORY FOLLOWS:

Shortly after 9 p.m. on Sunday, the Austin Police Department tweeted it was responding to a “Bomb Hotshot call” on the city’s southwest side. Austin-Travis County EMS (ATCEMS) officials also tweeted that an “explosion incident” occurred in the area and that ambulances had transported two patients. The patients were reportedly seriously injured but did not appear to have “life-threatening” injuries, officials stated.

APD responding to Bomb Hotshot call in the 4800 block of Dawn Song Dr. Two male patients transported with unknown injuries. Please avoid the area. Media staging area is 4635 SW Pkwy, corner of SW Pkwy and Boston Ln. APD PIO — Austin Police Dept (@Austin_Police) March 19, 2018

Multiple assets on a reported second explosion 4800 block Dawn Song Dr (2032) reports of 2 patients. Investigation if this is the same incident as already reported or a separate incident underway. More information to be provided when available. — ATCEMS (@ATCEMS) March 19, 2018

A short time later ATCEMS officials described the two victims as males in their 20s.

FINAL: Critical Incident @ 4800blk Dawn Song Dr (correct incident address), Only 1 incident location has been confirmed. #ATCEMSMedics have transported X2 ~20’s Males to SAMC w/serious, but not expected to be life-threatening injuries. Refer all inquires to @Austin_Police — ATCEMS (@ATCEMS) March 19, 2018

The reports come just hours after Austin Interim Police Chief Brian Manley announced an increased reward for information leading to the arrest of the person or people responsible for three package bomb explosions this month that left two people dead and two others injured.

Texas Capital Tonight’s Max Gordon tweeted the following photo from the scene of the reported explosion.

Picture from the scene after a reported explosion this evening in Southwest Austin pic.twitter.com/jFHBWusjPX — Max Gorden (@Max_Gorden) March 19, 2018

Chief Manley briefed reporters late Sunday night and confirmed that an explosion had occurred at a home in the 4800 block of Dawn Son Drive near Republic of Texas Drive. The chief said there is an obvious “blast site.”

Initial Statement from Chief Manley regarding explosion https://t.co/CCydXhmQ8e — Austin Police Dept (@Austin_Police) March 19, 2018

The chief also confirmed they are investigating a second incident involving a backpack. He said the bomb squad is in the process of clearing the backpack at this time. He offered no other details about the explosion and requested residents of the community to stay indoors until after sunrise on Monday. He cautioned people not to touch or approach any suspicious package.

He told reporters, “We’re not going to take questions because we simply just don’t know anything at this time.” The next briefing is scheduled for early Monday morning.

Officials have not yet confirmed if Sunday night’s explosion is connected to the previous explosions that left two people dead and two others injured.

A hospital spokesman at St. David’s Hospital confirmed they are treating two male patients who are stable at this time, KVUE’s Christy Millweard tweeted.

Spokesperson for @StDavidsHC confirms to me the two male patients are at St. David’s South Austin Medical Center- says both are stable – waiting to hear condition @KVUE — Christy Millweard (@ChristyM_KVUE) March 19, 2018

KVUE’s Kris Betts tweeted that one of the men may have nails in his leg from the explosion.

UPDATE: 2 men in their 20s hurt in reported explosion in SW Austin. Injuries don’t appear to be life -threatening. One man reported to have nails in his leg. — Kris Betts (@KrisB_KVUE) March 19, 2018

Earlier on Sunday, Austin police officers arrested a man for emailing a bomb threat to the Fair Market in East Austin on Saturday evening, NPR reported.

Prosecutors charged Trevor Weldon Ingram, 26, with making a terroristic threat.

East Austin is the area where two packages exploded on March 12 killing a 17-year-old young man and injuring his mother in the first explosion and a 70-year-old Hispanic woman in the second explosion.

The first explosion in the series of blasts in the Austin community occurred on March 2 and killed 39-year-old Anthony House.

Editor’s Note: This is a developing story and will be updated as new information becomes available.

Bob Price serves as associate editor and senior political news contributor for Breitbart Texas. He is a founding member of the Breitbart Texas team. Follow him on Twitter @BobPriceBBTX, Gab, and Facebook.