Record numbers spend more than 12 hours in A&E in Wales
The number of people spending more than 12 hours in accident and emergency in Wales is at its highest since records began in 2012.
Figures for January show it affected more than 3,000 people.
It comes as the number of people being seen at A&E across Wales within four hours improved slightly last month.
The figure of 82.3% is up from 81% in December, but is still well below the 95% Welsh government target.
In total, 73,199 people attended emergency departments last month.
The statistics refer to time taken until admission, transfer or discharge, not just the time it took for someone to be seen for the first time.
A Welsh government spokesman said emergency units are seeing increasingly more patients.
"Despite these increases in demand, the latest statistics for January show that eight out of 10 patients spent less than four hours in A&E units from arrival until admission, transfer or discharge," he said.
"However, the number of patients waiting over 12 hours is unacceptable. We expect health boards to work with local authorities and other partners to ensure that patients can be treated, admitted and discharged appropriately and receive safe and effective care."
Helen Birtwhistle, director of the Welsh NHS Confederation, said emergency units were under increasing pressure and a "system-wide change" in treatment is needed.