First Minister Nicola Sturgeon has said Scotland stands in solidarity with London following the ''heinous'' terrorist attack on Westminster.
T Kicks Off At Strathallan
Tens of thousands of festival goers have given T in the Park a warm welcome to its new home at Strathallan Castle
Revelers were warned to bring their wellies - for the inaugural year at Strathallan Castle.
Kasabian, David Guetta, Sam Smith, Mark Ronson and Fat Boy Slim are just some of the names appearing tonight, which is taking place at the Perthshire estate for the first time this year.
Organisers expect 85,000 people a day at the three-day event, with the likes of Avicii, Stereophonics, The Libertines, James Bay and Noel Gallagher's High Flying Birds also in the line-up.
Fans laden with rucksacks and tents began arriving at the campsite when it opened yesterday, with thousands more flocking to the site today as the first acts took to the stage.
Wellies were the footwear of choice for the early birds after mist and rain churned many of the site's walkways into mud.
But the low cloud gave way to sunshine as the afternoon wore on, lifting spirits - and volume levels - in the process.
Scots synth-pop band Prides got proceedings under way on the main stage, followed by The Cribs and The Wombats.
Organiser DF Concerts struck a deal to shift the 2015 festival after health and safety concerns about an underground oil pipeline at nearby Balado, where it had been held for 18 years.
Local councillors approved the plan in May despite opposition from some residents and environmental groups who expressed concern for ospreys at Strathallan.
Concerns were also raised about traffic arrangements for the event, and the potential for anti-social behaviour.
The festival runs until Sunday, with The Prodigy, Idlewild, The Script and The Proclaimers also set to perform.
Organisers have said they hope fans will enjoy the event's new setting.
The estate, which dates back to the 13th century, is owned by the Roberts family, who say staging the event will allow improvements to be made to the area.
They also reckon it will give tourism and businesses in the region a boost.
The maximum temperature forecast for today and Saturday is 18C, for Sunday it's 17C.
Telecoms firm BT is to create 31 jobs in Glasgow as part of a recruitment drive to transform customer service.
Two Canadian pilots have appeared in court accused of being under the influence of alcohol as they prepared to fly a passenger flight from Scotland.
The status quo ''is not an option'' for Scottish education in a review of how schools are run, ministers have said.
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