A teenager is in hospital in a serious condition after taking an "ecstasy-type tablet" with friends.

Officers have issued a drugs warning after the teenager and three friends became unwell in Perth on Friday night.

The 15-year-old was taken to Ninewells Hospital in Dundee at around 10pm where he is in a serious condition.

His friends were treated at Perth Royal Infirmary but were later discharged.

Tayside chief inspector Gary Ogilvie said: "We were alerted to the incident at around 10pm last night after the boy became unwell.

"Three of his friends also received medical treatment at Perth Royal Infirmary however have since been discharged.

"One line of enquiry is that all four boys had possibly consumed a type of ecstasy tablet.

"Officers are currently investigating the circumstances of this incident but in the meantime I would urge the public, especially those planning on going out socialising tonight to be aware of this incident and think twice of taking any unknown substance.

"There is always a risk when taking substances and the only way of staying safe is to avoid drugs altogether."

Police are asking anyone with information related to the incident to contact them on 101.

It comes two weeks after 16-year-old Shellie Callaghan died following a house party in Midlothian, where police believe she may have had access to "ecstasy-type tablets".

On Wednesday a 13-year-old girl was taken to hospital after suspected drugs misuse at a school in East Renfrewshire.