The fear that grips North American airports has heightened tensions and led to the arrest of a security guard whose attempt to check a uniformed police officer's credentials caused her to be handcuffed, strip-searched and criminally charged.

Until last Thursday, 37-year-old Sandra Turner made $9.53 an hour at her job at Toronto's Pearson airport. But her security credentials have been revoked as she awaits next month's court date when she will answer charges that she created a public disturbance.

The altercation that led to those charges began when the 5-foot-4 security guard tried to stop a police officer as he walked around her checkpoint. She says she tapped Constable Luis Simoes's elbow. The police say she grabbed him to get his attention.

There ensued an angry row that ended with dozens of gawking passersby witnessing Ms. Turner's arrest.

"I didn't do anything. To me, I was doing my job," she said, adding that she was "crying and embarrassed" as she was led away in handcuffs through her workplace of three years.

Since the terrorist attacks in New York and Washington, airport authorities across the continent have tried to step up security. In some cases, patience has grown short as the rules have grown long -- and tales of confusion, confrontation and continuing security breaches abound.

The changing climate is aimed at preventing further attacks. But some sharp items that could be used as weapons continue to sail through checkpoints.

Vilma Smith of Toronto said her husband was alarmed this weekend when he unpacked his carry-on luggage after flying from Toronto to Chicago.

"When he got to his hotel he said, 'My God, I had a box cutter on,' " she said.

Mitchell Smith forgot he was carrying the item he traditionally packs, she said. Terrorists used just such weapons to hijack the airplanes that destroyed New York's World Trade Center.

Meanwhile, in the aftermath of reports last week that steak knives are being handed out on flights, the Canadian government banned all metal knives except the rounded kind used for butter. For the most part, passengers now make do with plastic.

Ms. Turner says she was told she would be charged with assault before she was handcuffed and dragged through her workplace. She was taken to a nearby police station where she was searched and charged with creating a disturbance.

Constable Heather Andrews, a spokeswoman for the Peel police, said security guards "don't have the authority to physically detain or accost anyone."

She added that the disturbance caused by Ms. Turner's shouting jeopardized security at the checkpoint.

The Greater Toronto Airports Authority would not comment on the case. Speaking generally, a spokesman said it is just doing what is necessary to ensure security and that Transport Canada rules require everyone to show ID and submit to searches -- except for police.

But that is not the understanding of a security company contracted by the airport authority. "It's my understanding that we're to confirm that they are qualified officers," said Jim Crawford, manager for airport division of Wackenhut of Canada Ltd.

He added that Ms. Turner is not a troublemaker and has the company's full backing.

As a result of the stepped-up measures, passengers have varying perspectives on whether security is adequate, lax or overzealous:

Yesterday, Daniel Steel, arriving in Toronto after an almost three-hour flight from Houston, said security was "very thorough and complete."

"A gentleman in front of me had a key chain with a small pocketknife," said Mr. Steel, a 45-year-old banker. "The blade couldn't have been more than half an inch. They didn't confiscate the knife but they broke the blade."

Another passenger travelling from Chicago said the checkpoints were inadequate. "I just walked through security," said the 37-year-old man, who did not want his name used. He said he wasn't asked about his luggage, and no one checked his documents.

Upstairs, Colleen Machell, 40, and Richard McCleery, 38, waited in the check-in line for their transatlantic flight to London. Before leaving for the airport, they had cautiously removed several items that might have been seized by airport security.

They left behind scissors, razors, a corkscrew, and other small items that could conceivably be used as weapons.

"Why bring it, just to have them confiscate it?" Mr. McCleery asked.