The Scottish justice secretary has come under fire from a UK minister over his comments about anti-terror searches at Scottish train stations.
BTP officers have carried out over 14,000 searches in Scotland
Tom Harris has demanded an "unreserved apology" from Kenny MacAskill after Mr MacAskill accused British Transport Police (BTP) officers of harassment.
Glasgow MP Mr Harris said the criticism was "cynical and irresponsible".
Mr MacAskill told the BBC that he stood by his comments and would not be making an apology.
In a BBC interview on Sunday, the justice secretary had accused the transport police of following a "diktat from London".
He claimed the officers were "harassing" people, particularly those from ethnic minorities, which he said "deeply, deeply" troubled him.
But Mr Harris, the parliamentary under secretary of state for transport, told BBC Radio Scotland that Mr MacAskill was "playing politics with anti-terrorism operations".
He added that he had a large number of Asian voters in his constituency and had received "not one single complaint" from them.
Mr Harris asked: "Why is Kenny MacAskill launching such an unprovoked attack on the British Transport Police when he's not even picking up the phone to ask for an explanation of these figures?
"Kenny MacAskill is playing politics with anti-terrorism operations and at this period, when we are subject to who knows what kind of terrorist threat, it is outrageous for a minister to attack the transport police when all they are trying to do is protect the travelling public."
Mr MacAskill had cited figures which showed transport officers stopped 9,994 people and searched 4,636 vehicles at Scottish railway stations between 1 July and 14 December this year.
He contrasted that with statistics showing Scotland's eight police forces stopped and searched just 84 people and 51 vehicles in 2007.
Mr Harris, who is the MP for Glasgow South, has now sent a strongly-worded letter to Mr MacAskill.
It stated: "Terrorists have recently targeted transport infrastructure in this country (London Underground and Glasgow Airport) and it is therefore right that the BTP are vigilant and do everything practicable within its authority to disrupt and deter terrorist activity.
"I can only conclude that the vast majority of the travelling public in Scotland feel reassured rather than threatened.
"Your attempts to invoke the prospect of discontent in community relations is both cynical and irresponsible."
Mr MacAskill, who said he had not yet received the letter, insisted he had been right to raise the issue, and said he had no plans to apologise.
"What we have to do in Scotland is make sure we make Scotland safe and strong," he told the BBC.
"I regret very much that a London minister - given that we have been co-operating with them fully and with governments internationally to combat terrorism - should take this position.
"I have no complaints of the ordinary members of British Transport Police - it's the ethos and diktat coming from London."
He said he had been told that British Transport Police had no information on potential terrorism that was not available to the government.
And Mr MacAskill questioned why similar attention was not being paid to bus stations and the Glasgow underground.
Kenny MacAskill said he stood by his comments
He said: "The fact of the matter is that 2% of the Scottish population is an ethnic minority is the black and Asian community yet they have suffered 12% of the searches."
Denying that he was seeking to embarrass a London minister, he said: "No, we are doing what we have to to tackle terrorism.
"We live in difficult times, we have to ensure we protect not only our own community but every community."
He added that while it was the responsibility of the Scottish Government to guard against terrorism, it also had a responsibility to protect communities from "what they may perceive" as harassment or intimidation.