Copyright © 2018, ABC Radio. All rights reserved. iStock/Thinkstock(AUSTIN) — The man accused of killing two and injuring four by planting explosives in and around Austin, Texas, has killed himself with another bomb after local and federal agents closed in on him early Wednesday morning.Police said they could not publicly identify the suspect yet and remain concerned that he may have planted more explosive packages elsewhere.The confrontation occurred in Round Rock, approximately 20 miles north of Austin, where the string of bomb attacks began almost three weeks ago.Police zeroed in on the eventual suspect as a person of interest over the last 24 to 36 hours, eventually locating his vehicle with the help of surveillance teams, authorities said at a press conference early Wednesday.Local and federal authorities took up positions near a hotel where the suspect had stopped his vehicle, awaiting tactical teams to help apprehend him.The suspect, after beginning to drive away, stopped on the side of the road and as Austin SWAT team members approached he detonated a device while inside his vehicle. One officer was knocked back and suffered minor injuries, and another fired at the suspect.“We cannot name the suspect at this time because he has not been positively identified yet by the medical examiner, and next of kin have not yet been notified,” Austin Police Chief Brian Manley said. “There will be a lengthy investigation that will take place regarding the officer-involved shooting.”Authorities confirmed that the suspect was a 24-year-old white male but declined to say where he was from.Residents of Austin had been on edge ever since the bombings began March 2, killing two people and injuring at least four others.The first three involved packages left on porches, while the fourth, which injured two men ages 22 and 23 on Sunday night, was detonated by a trip wire tied to an explosive device.On Tuesday, an unexploded bomb was discovered at a FedEx facility in Austin, two sources told ABC News. That’s the sixth device tied to the serial bomber — five package bombs and the device tethered to the trip wire.This is a breaking story. Please check back for updates throughout the day.