A pair of hospitals and a college were recipients of threats of violence on back-to-back-to-back days this week in Southern California. 

Now, officials are investigating all three incidents and are being extra vigilant in case more cases like the three that took place over the last three days are reported. 

Wednesday: Loma Linda Children’s Hospital

The first incident occurred on Wednesday evening at Loma Linda Children’s Hospital.

In this case, the San Bernardino County Sheriff’s Department stated that they had been made aware of reports of a “possibl[y] armed individual” around 6:35 p.m.

Shortly after, a hospital official confirmed that authorities were responding to the scene as part of an “active investigation” that involved hundreds of law enforcement officers.

Video footage from Sky5 showed a very large police presence outside the hospital as dozens of police cruisers, armed vehicles and heavily armed officers wearing tactical gear responded to the scene.

Authorities warned the public to avoid the area while the investigation on the hospital campus was active, and potential patients were encouraged to visit other local medical centers.

The scene was cleared by around 9 p.m.

In the wake of the threat, the sheriff’s department took to social media to declare that no shots were heard and no injuries reported.

They later stated that the initial reports of an active shooter stemmed from a “swatting call,” which is a dangerous, illegal prank in which a caller claims there is a life-threatening emergency at a specific location, eliciting a massive police response.

Authorities confirmed that they are already pursuing a lead on the possible source of the hoax.

Thursday: Claremont McKenna College

Less than 24 hours after the Loma Linda incident, students and faculty at Claremont McKenna College were forced to shelter in place while police responded to reports of a possible shooter on campus.

The university’s student-run newspaper, The Student Life, reported that campus safety officials notified the school community just before 5 p.m., saying there was police activity and a potential shooter. The shelter in place warning followed shortly afterwards.

“The caller told dispatch that they were in a restroom at Claremont McKenna College Campus, holding someone captive and threatening to harm them,” officials with the Claremont Police Department said in a news release. “They also stated that they had a bomb and we’re going to walk around with a rifle and shoot anyone they saw on the campus.”

Sky5 footage showed that a SWAT Team responded to the area along with dozens of officers from different departments, including the Claremont, La Verne, Ontario and Upland police departments. Students were seen being escorted out of at least one campus building with their hands on their heads.

Thursday evening classes were canceled due to the incident. Classes resumed on Friday morning, according to The Student Life.

An all clear was given and the shelter-in-place order was lifted two hours after the threat was first received. No person with a weapon or victims were located.

Further investigation into the incident led authorities to determine that it was a “swatting” call that required the deployment of “extensive resources,” but no further information was immediately released.

KTLA has put in a request for comment with the Claremont Police Department for more details on the case.

Friday: Huntington Hospital

This week’s third incident occurred at Huntington Hospital in Pasadena on Friday.

A spokesperson for the City of Pasadena told KTLA that a 33-year-old man called in a threat of a “violent attack” to the hospital around 2 p.m., which caused it to go into lockdown.

The man had been admitted to the medical center earlier in the day, officials stated.

Hospital employees received a text alerting them of a “Code Silver” threat, which indicates a possible active shooter or hostage situation. Incoming ambulances were redirected to other nearby hospitals and both patients and visitors were not permitted to enter the hospital during the lockdown, which lasted for hours and affected the emergency room.

Multiple police squad cars were seen outside the hospital as officers began investigating.

Authorities quickly launched a probe into the incident and determined it was not a “swatting” call but was a legitimate threat.

The man was later taken into custody by police in Los Angeles, officials said. Media reports identified him as Jose Jurado.

On Saturday, a Pasadena city official told KTLA that they could “confidently” say that the two incidents in Loma Linda and Claremont are not believed to be related to this one.

The Department of Homeland Security has released guidelines that detail what a “swatting” call is, what to do if a threat is received and steps to take after an incident. Click here to view them.

Sofia Pop Perez contributed to this report.