Two artefacts valued at £1.8m have been stolen from Durham University's Oriental Museum in a night-time raid.
Thieves got into the museum's Malcolm MacDonald Gallery late on Thursday, escaping with an 18th Century jade bowl and porcelain sculpture.
Museum officials described the objects as "highly significant" examples of the Qing Dynasty.
Two men and a woman have been arrested in the West Midlands in connection with the burglary.
They have been brought to a Durham police station for questioning. The two artefacts have not been recovered.
Det Ch Insp Traci McNally said: "We are still trying to locate several outstanding suspects in relation to this investigation.
"We believe those individuals would be aware of the police investigation and would urge them to contact Durham Police on 101 without delay."
Both stolen items are from the Qing Dynasty, the last imperial dynasty in China, which ruled from 1644 to 1911.
The large green jade bowl, dating from 1769, is from the collection of Sir Charles Hardinge, a British collector of jades and hardstones. A Chinese poem is written inside.
The thieves also took a Dehua porcelain sculpture, with a cream white glaze, of seven fairies in a boat, which is 30cm (11.8ins) in both height and length.
A spokeswoman for Durham Police said the estimated value of both pieces was £1.8m. She said it was possible the items had been stolen to order for a foreign collector.
Museum curator Dr Craig Barclay said: "We are extremely upset to have fallen victim to such a serious crime.
"The two pieces are highly significant in that they are fine examples of artefacts from the Qing Dynasty in the mediums of porcelain and hard stone.
"We very much hope that police will be able to recover them and we urge anybody who may have any information about their whereabouts to contact the police immediately."
The museum will be closed until further notice.
Dr Barclay added: "We are very sorry that our customers have been affected by this incident and intend to reopen as soon as possible."
The university has been targeted by art thieves in the past, most notably when a rare copy of Shakespeare's First Folio was taken in 1998.
County Durham antiques dealer Raymond Scott was later convicted of handling stolen goods. He was found dead in prison earlier this year.