Two women are being treated for knife wounds after an attack at a house in Shropshire.
It happened in Newchurch Road, in Wellington, on Monday evening.
One of the women, in her 60s, was taken to the Princess Royal Hospital, in Telford, where she underwent surgery on Tuesday afternoon.
Her condition is described as serious.
The second woman is being treated at the same hospital for minor injuries.
West Mercia Police have arrested a teenage man in connection with the incident.
Detective Sergeant Ian Rutherford from Telford CID said they were still trying to find a motive.
"We've had officers out taking statements from the family and carrying out house to house inquiries and we also have a team in the Birmingham area making further inquiries," he said.