The city of Austin was once again stunned by another explosion in a neighborhood Sunday night. This is the fourth explosion this month. Emergency workers responded to the scene Sunday night where two men were injured as a result of the blast. They were taken to an area hospital with serious, but non-life threatening injuries and are now listed in 'good' condition. Police, again, strongly warned the public to report any object that seems out of place. Officers say this last device may have been triggered by a trip wire. But they say they can't confirm that, until they fully process the scene in the light of day. Officers shut down the neighborhood and have asked residents to stay indoors, until they can comb through the rest of the area to make sure it's safe.