Airbnb’s chief executive has said the company will ban “party houses” following a deadly shooting at a Halloween party held at an Airbnb rental home in California.

In a series of tweets, Brian Chesky said on Saturday that the San Francisco-based company would expand manual screening of “high risk” reservations and remove guests who fail to comply with policies banning parties at Airbnb rental homes.

He also said the company is forming a “rapid response team” when complaints of unauthorised parties come in.

“We must do better, and we will. This is unacceptable,” he tweeted.

Five people died after a Thursday-night shooting that sent some 100 terrified partygoers running for their lives in the San Francisco suburb of Orinda.

Brian Chesky (@bchesky)

Starting today, we are banning “party houses” and we are redoubling our efforts to combat unauthorized parties and get rid of abusive host and guest conduct, including conduct that leads to the terrible events we saw in Orinda. Here is what we are doing:

November 2, 2019

The four-bedroom home had been rented on Airbnb by a woman who told the owner her dozen family members had asthma and needed to escape smoke from a wildfire, a person with knowledge of the transaction told the Associated Press. A fire burning in Sonoma County about 97km (60 miles) north of Orinda earlier in the week fouled the air over a wide area.

The owner was suspicious of a one-night rental on Halloween and before agreeing reminded the renter that no parties were allowed, said the person with knowledge of the transaction, who was not authorised to publicly disclose the information and spoke on condition of anonymity.

The owner, Michael Wang, said his wife contacted the renter on Thursday night after neighbours alerted them to the party. The renter said there were only a dozen people at the home but Wang said he could see more people on video from his doorbell camera.

“We called the police. They were on the way to go there to stop them, but before we got there the neighbour already sent us a message saying there was a shooting,” he told the Chronicle.

No arrests have been made and there was no immediate word on a motive for the attack. Two guns were found at the property, authorities said.

Three people, all from the Bay area, died at the scene and a fourth died in hospital, authorities initially said. The Contra Costa County sheriff’s office identified them Friday evening as Tiyon Farley, 22, of Antioch; Omar Taylor, 24, of Pittsburg; Ramon Hill Jr, 23; and Javin County, 29. The sheriff’s office identified a fifth victim, 19-year-old Oshiana Tompkins of Vallejo and Hercules, late Friday night, saying she died in hospital.

Taylor’s father, Omar Taylor Sr, said his son was hired to play music at the party.

“Wrong place, wrong time,” he told the East Bay Times.

Other people were wounded by gunshots or injured in the panic that followed, authorities said.

The party at the four-bedroom house apparently was advertised on social media as an “Airbnb mansion party”.

Orinda, with a population of about 20,000, requires short-term rental hosts to register with the city annually and pay an occupancy tax. The maximum occupancy is 13 people.

Orinda city documents show officials issued violations in March for exceeding the home’s maximum occupancy and illegal parking. City manager Steve Salomon said the homeowner had resolved previous complaints lodged in February over occupancy and noise and in July over overflowing trash.

Airbnb is “urgently investigating” what happened, spokesman Ben Breit said in an email.

Airbnb has banned the renter from its platform and the home has been removed as a listing, he said.

One attendee said he was enjoying the music and watching people dance when he heard shots and people started running.

The screaming seemed to last forever, said Devan, who asked that his last name not be used because he feared for his safety.

“Everybody started running, scrambling,” he said. “People were just collapsing and friends were helping friends. It was a scary situation and then as everyone is panicking and stuff, there were more shots.”

Devan shot a video posted to Instagram that showed a wounded man on the ground and a police officer standing over him and a woman saying she needs to go to the hospital “because my hand’s been blown off”.

On Friday, police tape surrounded the block as people came to collect their cars and other belongings. One woman in tears told reporters the father of her child had been killed. She left before giving her name.

Romond Reynolds picked up the car of his son, 24-year-old Armani Reynolds, who he said was left comatose by the shooting.

“All I know is that he’s a victim and was at the wrong place at the wrong time,” Reynolds said.

Neighbour Shahram Saki, 61, said in a phone interview that some fleeing partygoers hid in the bushes in his front yard and others begged to be let into his home.

“They were screaming for help. I told them, ‘You gotta get out of here’,” Saki said. “I was scared to death, anything could have happened.”