It's thought the attack could last several days.
Clutha Report Calls For Flight Recorders
The official report into the Clutha tragedy in Glasgow in which 10 people died has renewed calls for police helicopters to be fitted with flight recording equipment.
The long-awaited conclusions of the Air Accidents Investigation Branch confirmed that the helicopter which crashed in to the packed pub did not have a flight recorder.
Following a fatal air ambulance crash in July 1998 the AAIB recommended that the Civil Aviation Authority should "encourage the development'' of lightweight and low-cost flight recorders and "consider'' whether they should be used in emergency service helicopters.
Similar statements were made by the AAIB to international aviation regulators following private helicopter crashes in July 2003 and January 2005.
Following the Clutha crash, the AAIB has gone further and recommended that the CAA "requires'' all police helicopters to be "equipped with a recording capability that captures data, audio and images in crash survivable memory''.
But new helicopters should only be required to have full black box flight recorders from January 2018, the AAIB added.
The AAIB report concluded that the pilot did not follow emergency procedures after a fuel warning in the cockpit.
Investigators found that two fuel supply switches were off yet the helicopter continued to carry out three surveillance jobs over nearby Lanarkshire rather than land.
The pilot, David Traill, who was attached to Police Scotland's air support unit, was a highly experienced former RAF and training pilot with more than 5,500 flying hours in helicopters.
The report stated that it remains unclear why the fuel supply switches were in the off position, ultimately leading to both engines cutting out.
It also found that the helicopter's low fuel warnings were triggered and acknowledged five times during the flight.
The AAIB added that the pilot did not complete the emergency shutdown checklist following the first engine failure. The second engine failed 32 seconds later.
It was not known why a successful autorotation - the landing of a helicopter without power - was not achieved.
Read all the details here: https://www.gov.uk/aaib-reports/aircraft-accident-report-aar-3-2015-g-spao-29-november-2013
Sturgeon says Trump is on the "wrong side" of the debate.
The boys were found inside the Sainsbury's store at 2am on Tuesday.
The incident, which happened at Ibrox station, was reported to British Transport Police before 8pm on Saturday.
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