Boyle, 48, is the favorite to win the "Britain's Got Talent" competition this weekend.
The Times of London said she was heard yelling at a reporter in front of guests at the Wembley Plaza Hotel: "How (expletive) dare you! You can't (expletive) talk to me like that."
The Sun newspaper said police stationed at the hotel then went to Boyle and asked if there was a problem, to which she reportedly shouted, "Of course there's a (expletive) problem."
However, Boyle's spokeswoman is downplaying the incident and laying blame on the reporter.
"A journalist from a tabloid paper provoked her. The police just happened to be at the hotel and escorted said journalist out after making sure Susan was OK," The Times quoted Boyle's representative as saying.
"Talent" judges Piers Morgan and Amanda Holden told the U.S. television program "Inside Edition" Boyle seems to be buckling under the tremendous pressure her new found fame has brought her.
"She's been in tears repeatedly," Morgan said in an interview to air Thursday. "And, as of yesterday, she was packing her bags."
However, Morgan said he got a message to Boyle advising her: "Please, relax… Keep quiet. Don't read the newspapers. Don't watch television. Just get to Saturday and your one performance."
"Inside Edition" said both Morgan and Holden insisted reports of Boyle's alleged meltdown have been exaggerated.
Holden added Boyle has been the victim of "public bullying."
"Everyone should just step back," she said.