The Austin police has directed the neighborhood of southwest Austin to be at home till the time of 10 a.m. Monday after they started investigation of fourth explosion within a month, the last one that hit Texas’ capital which injured at least two men.

The police conducted a late-night news conference on Sunday, the Chief of Austin Police Brian Manley claimed that there was high possibility that a tripwire was used to trigger the device in Travis County.

“We will not be able to send school buses into the neighborhood on Monday,” he said. “In addition to that, we’re going to ask the residents in the Travis County neighborhood to stay in your homes tomorrow morning and give us the opportunity to process the scene once the sun comes up.”

Manley asked the community “to have an extra level of vigilance and pay attention to any suspicious device whether it be a package, a bag, a backpack, anything that looks out of place and do not approach it.”

Police believe that the incident is completely related to a string related to unsolved package of bombings. It killed atleast two people and other two were injured.

On the morning of March 2, Stephen House aged 39 was killed and after that on March 12, Draylen Mason died. His age was 17. Both people were African-American members belonging to same church according to Nelson Linder, the local NAACP chapter president, was quoted by NBC News as saying.

Mason’s mother, aged 41 year, was also injured in the explosion. And on March 12, a third bomb rip apart injuring critically a 75 year old Hispanic woman, Esperanza Herrera.

The third explosion’s target victim seemed to be someone connected House’s or Mason’s families according to Linder. But he declined to provide additional details about that.

When asked whether the bombings were racially motivated Manley commented that its pretty possible.

Hence, the police gave orders to the neighborhood to stay inside the home until 10 a.m. on Monday just after the fourth explosion within a month.

“We will not be able to send school buses into the neighborhood on Monday,” he said. “In addition to that, we’re going to ask the residents in the Travis County neighborhood to stay in your homes tomorrow morning and give us the opportunity to process the scene once the sun comes up.”

The men who were injured in the Sunday blast are being treated for non-life threatening injuries, officials said.

Manley asked the community “to have an extra level of vigilance and pay attention to any suspicious device whether it be a package, a bag, a backpack, anything that looks out of place and do not approach it.”