Published: Aug 15, 2011 8:34 PM EDT

LONDON (AP) - A Polish man is suspected of killing his wife, their two children, his father-in-law and two family friends in a frenzied stabbing spree, the deadliest crime in memory on the Channel Island of Jersey, police and local residents said Monday.
    
Detective Supt. Stewart Gull of Jersey Police said a man, two women and three young children stabbed to death Sunday came from two families, one of them Polish.
    
He said the other family was from Jersey. Polish officials said they believed all the victims were of Polish origin.
    
A 30-year-old man - a member of the Polish family - has been arrested on suspicion of murder. He was in a hospital Monday after undergoing surgery for knife injuries that witnesses said were self inflicted. Police were waiting to question him.
    
Gull said four victims were found inside the Polish family's apartment on a secluded residential street in the island's capital, St. Helier. Two were found outside the building.
    
He said it was too early to speculate about a motive for the killings.
    
Britain's Press Association news agency identified the suspect as Damian Rzeszowski and said that his slain wife was named Izabela.
    
It cited family friend Jakub Bartus, who was speaking at a Catholic church Mass in St. Martin, near St. Helier. Bartus was quoted as saying: "There are lots of questions that need to be answered. It's such a tragedy. I can't understand why the kids were involved."
    
Bartus' wife Marlena said two of the victims were Damian and Izabela's children - which she identified as an approximately 2-year-old boy and a 5- or 6-year-old girl. The other victims were identified by PA as Izabela's father, as well as a family friend and the friend's child.
    
Marlena Bartus said her own son used to play with Damian and Izabela's child as the two were about the same age.
    
Neighbors reported hearing screams before police and ambulances arrived Sunday.
    
Bryan Ogesa, who lives in the same apartment building, said he heard screaming and ran outside to see a man with a knife chasing a woman, and another woman lying on the ground.
    
"She was responsive, but just mumbling," he said. "That's when the guy started coming towards us. He was mumbling as well."
    
Ogesa said he fought the man off with a traffic cone before the attacker turned the knife on himself.
    
Another witness, Andre Thorpe, said he later saw police running from the building carrying a small child.
    
"When the paramedic came back her shirt was covered in blood," he said.
    
Police on the island - a tax haven and holiday destination 14 miles (22 kilometers) off France's Normandy coast - say the crime is the deadliest in living memory.
    
Jersey, a 45-square-mile (118-square-kilometer) British Crown dependency with a population of 90,000, had not had a murder since 2004, when a 19-year-old man originally from Northern Ireland tried to rape, then kicked to death, a 35-year-old nurse outside her home. It was the first murder in Jersey since the 1970s.
    
Between 3,000 and 5,000 Polish nationals live on Jersey.
    
Chief Minister Terry Le Sueur said the crime had "greatly shocked the island's community." He said anyone who needed counseling would receive it.
    
"Jersey is a very safe place and events of this terrible nature are very rare," he said.

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