Border agency officials' powers were extended by a 1999 act of Parliament
An immigration group has condemned UK Border Agency powers following a report of a raid on the home of a Tongan ex-employee of the attorney general.
The Joint Council for the Welfare of Immigrants said the officials had "some police powers" that were "too much".
The Mail on Sunday reported a raid on the west London home of Loloahi Tapui, investigated over a report she had worked illegally for Baroness Scotland.
The Home Office said extending border officers' powers had been "necessary".
The council's chief executive Habib Rahman said immigration officials could "misuse" their authority.
He also said he was not supportive of these type of raids being carried out by UK Border Agency officials.
"We have been complaining about raids for a long time," he said.
"The government has given some police powers to border officials, and they have too much power now.
"Border officials also have the power of customs officers as well, and if you give them all this draconian authority they may misuse it.
"We have seen cases where the border agency is dealing with cases that they're not trained for, like the police are.
"We think there will be training issues, and that the law will not be implemented like it should be."
Mr Rahman also said the JCWI was against raids on homes where immigration was an issue.
"Innocent people can get caught up in the activity, and it spreads fear in the community. The people they are looking for can just run away.
"There should be more intelligent ways of dealing with immigration issues or irregularities."
And Mr Rahman said the situation surrounding Baroness Scotland's former cleaner, a Tongan woman, was a "godsend for our argument".
He added: "Employers and work agencies have been complaining to us about the fact that they are expected to act like immigration officers themselves.
"This case shows how difficult it is to implement the nuances of immigration law, if a problem can occur with a government minister. It's not easy."
A spokeswoman for the Home Office said the Immigration and Asylum Act 1999 provided extended powers to immigration officers "allowing them, in certain circumstances, to search persons and premises, to enter premises for the purposes of searching and for arresting persons and to seize and retain relevant material".
"The provision of these powers to immigration officers is necessary to allow the immigration service to make use of existing powers of arrest and to operate, in appropriate circumstances, without accompanying police when conducting operational visits."
The spokeswoman also said that a warrant must only be served by a police officer or designated arrest trained officer of immigration officer rank or above.