A prank 911 call Tuesday led Palo Alto police to believe that a Facebook cyber-security executive in California had shot his wife, tied up his kids and planted “pipe bombs all over the place.”

At least 10 vehicles from the Palo Alto Police Department, the Stanford Department of Public Safety and a Palo Alto Fire Department combined, responded to a house of the executive, after the prankster called up the emergency hotline number, pretending to be the executive who had assaulted his wife with an assault rifle.

Police Agent Marianna Villaescusa, who was in charge of negotiating with the caller, said the call came in around 9:15 p.m. local time (12:15 a.m. EST Wednesday) and stayed on the phone till 10:02 p.m. local time (1:02 a.m. EST Wednesday). Although he “didn’t talk much” he told the negotiator that he will kill anyone who came near him or tried to help him, local newspaper Daily Post reported. 

Believing the threat to be real, the police cordoned off nearby areas after they responded to the scene. The unnamed Facebook employee, believed to be in his 30s, was seen coming out of his two-bedroom house after the police ordered him to do so over the loudspeaker. The man, who calmly agreed to get handcuffed, told the police that he had no idea what was going on and why he was being detained.

A woman, of a similar age as the man, living in a separate unit from the man’s house, was also briefly detained by police. The relationship between the man and woman was not disclosed.

As the man sorted out the matter with authorities, two teams of police officers carrying a special shield entered the house and thoroughly scanned it. No explosives were found inside the man’s residence and an all-clear was declared at the scene at 10:15 p.m. local time (1:15 a.m. EST Wednesday).

The police concluded that the call was part of a prank called “swatting,” which is essentially when an individual falsely directs emergency services of another state to a specific location, by making up a believable crisis or danger.

The prankster has not been identified as of yet. The response to Tuesday’s prank call could be labeled by some as a waste of police resources that could have caused a delayed response to other real-life situations. But, Villaescusa said it acted as a drill for her and the entire SWAT team.

It also called into question the preparedness of the fire department, who have been trained to assist police during shooter incidents. After getting back to their station following the prank call events, the police discussed potential improvements they could make if such a situation arises next time.

Villaescusa said instances of swatting was not unfamiliar territory for police in Palo Alto. In March 2018, someone called a hoax school shooting threat from a teenager’s lost cellphone, causing authorities to lockdown Palo Alto High School for some time.