A 23-year-old man is under police guard in hospital after his girlfriend’s father was shot dead and her mother severely wounded at their home in a Cornish hamlet.

Adam Hustler, 41, a successful businessman, died on Saturday night at Porth Kea House, his six-bedroom home near Truro. His wife Amanda, 40, was shot twice in the back and is critically ill in hospital.

The couple’s two teenage daughters, who were in the house at the time, were unhurt. A man, said to be the boyfriend of Danielle Hustler, 18, was arrested after a police raid on his flat in Newbridge, near Penzance, at 5am yesterday.

Detectives are waiting to question the man, who is recovering from a head wound. He is believed to have tried to shoot himself with a .22 rifle, which police seized during the raid.

Neighbours in Porth Kea said that the Hustlers were Jehovah’s Witnesses. Mr Hustler was the managing director of a drain-cleaning company called Clear-Flow, where Danielle recently started work as an engineer.

The noise of the attack, shortly before 9.50pm, was masked by the sound of fireworks marking the end of Truro’s annual carnival. The alarm is believed to have been raised by Danielle and her 16-year-old sister Abigail.

More than 40 armed police and officers trained as negotiators sealed off the hamlet of 20 homes after the 999 call. Mr Hustler died at the Royal Cornwall Hospital in Treliske. His wife was later transferred to Derriford Hospital, Plymouth, where she was said to be in a critical condition.

Jehovah’s Witnesses said prayers for the family at the Kingdom Hall in Truro yesterday morning. Mr Hustler’s brothers, Christopher, Timothy and James, are also members but were too upset to attend the service.

Tim Mears, a member of the congregation, said: “We are all shaken to the core because this is a beautiful little place where you would never expect anything as terrible as this to happen. The whole family have been Jehovah’s Witnesses for generations and I knew Adam as a father and a friend. He was a lovely man who was a loving father and a faithful and loyal husband. We are all praying for Amanda, who is a wonderful, loving person. We hope her injuries are not too severe.”

The shooting has shocked Porth Kea, which is home to fewer than 100 people. One resident, Marie Laity, 32, said: “We have heard it is something to do with the daughter’s boyfriend. I did not even hear anything – the only bangs we heard were from the fireworks at the Truro carnival.”

Tomas Hill, a county councillor, said that Mr Hustler had just moved in after renovating the house. “He had just finished and was looking forward to setting up a real family home – a dedicated family man. It is one of the safest places in Cornwall, so for something like this to happen is a complete shock for everybody.”

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