A tiger on the loose among garden allotments. Panicked residents summoning armed police ill-equipped to deal with a dangerous predator. And, behind it all, Germany’s self-proclaimed “Tiger Queen” and her private menagerie.

In startling scenes over the weekend in the eastern town of Schkeuditz, near Leipzig airport, the mix proved fatal for a big cat named Sandokan and left a keeper seriously injured.

On Sunday afternoon, a warm spring day when many hobby gardeners were tending to their flower beds, the tiger attacked a 72-year-old man at an enclosure kept by the former tamer Carmen Zander and escaped.

Officers alerted to the scene by panicked neighbours tracked the animal down to a nearby allotment complex and killed it about 30 minutes after it had escaped “to prevent danger to those present”, police said.

Witnesses said officers climbed on to the roof of a car and fired three shots at the tiger, which had been lying just a few metres from a small fence bordering the gardens.

“Our paradise was shattered,” Silvia Kaempf, 68, who has a shed in the neighbouring allotment association, told local media.

The keeper, who police said had been in the tiger enclosure “with permission”, is reported to still be in hospital with severe scratches and bites and is unable to answer investigators’ questions.

A spokesperson said the police did not have a veterinarian or a stun gun at their disposal at the time of the escape, leaving only lethal means to restore public order. Prosecutors said no inquiry was planned against the officers who killed the animal.

But the regional public prosecutor’s office said it had opened an investigation into suspected negligent bodily harm against Zander, 52, over possible breaches of safety protocols.

The mayor of the Dölzig district where Zander lives with the tigers, Thomas Druskat, called for the immediate removal of the enclosure. “It’s unthinkable what might have happened if other people had been injured,” he told the newspaper Leipziger Volkszeitung.

Zander, who was not present at the time of the attack, reportedly worked for 15 years as a circus tiger tamer but stopped touring about three years ago. She expressed her shock over the week’s events, and avowed her love for her tigers.

“It’s actually every animal trainer’s worst nightmare,” she told the public broadcaster MDR in reference to the attack and its consequences, saying she was also worried about her injured colleague.

Zander’s website, which was still up this week advertising “wonderful” and “unforgettable” tiger-petting events for the public, features short biographies of each of her animals. Three tigers apart from Sandokan were listed as having died in recent years.

Sandokan was a nine-year-old, 280kg “majestic” Bengal-Siberian mix but was “a scaredy-cat” that could “quickly become overwhelmed and insecure” and “be triggered more quickly and unexpectedly” than the other animals.

“That’s why I need to be extremely sensitive and empathetic when training him, so that he feels secure with me,” Zander wrote, saying with the right treatment Sandokan reverted to being “a lovely, cuddly chap again”.

The website said that Zander had won multiple prizes at the Monte Carlo circus festival and featured a picture of her with Princess Stéphanie of Monaco.

However, she has previously faced scrutiny for the animals’ living conditions at the enclosure in an industrial zone of Schkeuditz, where she has kept tigers since 2016. The district administration office said there were eight tigers living at the facility.

A spokesperson for the office told Spiegel magazine that it had been “working for some time to improve the conditions in which the tigers are kept”.

Recently, Zander had been asked to “comply with the regulations in such a way that all animals have access to the required indoor and outdoor space, or to reduce the number of animals to fit the space currently available”.

The spokesperson said it was not yet clear what would happen with the animals as “no findings have yet been released regarding the investigation into the cause of the incident”.

The German Animal Protection Association called for stronger legal protections governing keeping wild animals, including a ban in some cases.

The animal rights group Peta, which has long criticised Zander, said veterinary authorities “share responsibility for this tragic incident” by having failed to act against the facility sooner and demanded that the remaining animals there be confiscated.

Yvonne Würz, a Peta adviser on zoos and circuses, criticised how Zander kept the big cats, telling local media: “The tigers are confined to a tiny space in their enclosure, in bare metal cages, and deprived of everything that would constitute a species-appropriate life for a tiger.”

Zander insisted her enclosure offered more hospitable conditions to those usually experienced by tigers in captivity. “The difference compared to a zoo environment is that my animals are always together and I don’t keep them in solitary confinement,” she said.

Zander relies on donations to care for the tigers, as well as the help of friends.

She said she dreamed of having her own tiger park, partly to raise awareness about the endangered species, and wondered why animal rights activists were not interested in finding a suitable solution for the tigers with her as their keeper.

If the animals were taken away from her, she said, they would be emotionally devastated. “They would become apathetic and refuse to eat. They would call out for me for days on end, withdraw into themselves and die.”

Zander did not respond to a Guardian request for comment.