Extra security measures are to be put in place for Scotland's World Cup qualifier against England in Glasgow this weekend in the wake of recent terrorist attacks.The Scottish Football Association (SFA) said the safety of all fans was "paramount" for the match at Hampden Park on Saturday.A series of outer cordons will be set up around the stadium to ensure only ticket holders are in the area, while bag and body searches will be in place.The SFA said it has been speaking with counterparts at the FA and Police Scotland and gates at the ground will now open at 3pm ahead of the 5pm kick-off.A request has also been made to governing body UEFA for a minute's silence to be held before the start of the match in memory of the victims of the Manchester and London Bridge attacks.An SFA spokesman said: " The safety of fans is of paramount importance to the Scottish FA and a range of measures will be implemented as part of an enhanced security operation. "These increased security measures at Hampden Park will include bag and people searches, and may result in delays in entering the stadium."Fans should expect to be searched at the outer cordons at Aikenhead Road, Prospecthill Road, Mount Annan Drive, Somerville Drive and Letherby Drive, with additional bag searches at the turnstiles."To accommodate these increased measures, gates will now open at 3pm, half an hour earlier than originally planned. Fans are reminded that the match is sold out and are therefore encouraged to arrive early to ensure that they are in their seats for kick-off."Scotland fans will be directed to use trains to Mount Florida station before and after the game, while England supporters will use King's Park.Free buses are also being laid on for fans from Glasgow city centre to the stadium before and after the match.Chief Superintendent John McBride is leading the operation for British Transport Police.He said: "Our policing operation will stretch the breadth of the nation and will involve a large number of officers."We want spectators to have a fun and enjoyable journey towards this match and will be on hand if they need assistance. Likewise, we will also be taking a zero-tolerance approach towards any individuals or groups who exhibit anti-social or criminal behaviour. There is no place for hooligan or intimidating behaviour and we will be taking firm action against those who are out to cause trouble."I would like to remind passengers travelling longer distances that there will be few trains departing after the final whistle. Therefore, I would urge them to plan ahead and make sure they have booked accommodation or alternative travel options."Passengers are of course the eyes and ears of the rail network and I would ask them to remain vigilant on their journey and report suspicious behaviour to us."