By KIERAN GRANT, TORONTO SUN

The Backstreet Boys are expected to play here tonight, though yesterday's attacks on the U.S. have thrown the local concert schedule into disarray.

Promoters began announcing show cancellations within hours of the news, as flights were grounded and security at the U.S.-Canada border was tightened. Others were uncertain as to whether performers would be able to appear.

Among the latter category were the Backstreet Boys, scheduled to perform at the Air Canada Centre tonight, tomorrow and Friday.

As of late yesterday, the Toronto office of promoters Clear Channel Entertainment reported that they'd received no instructions to postpone from the group or their label, Zomba/Jive, and that, pending further notice, the shows were still a go.

Several of the Backstreet Boys were reportedly already in Toronto, though all the members of the group weren't believed to have crossed the border. Zomba Records Canada was unavailable for comment, as they'd closed their Toronto headquarters for the day.

Clear Channel, whose head office is in New York City, did announce that the on-sale ticket date for U2's Oct. 13 show at Copps Coliseum in Hamilton, originally slated for Saturday, would be postponed until further notice.

Also up in the air is L.A. Latin-funk band Ozomatli's show at the Opera House tonight: At last check the band was stuck at the Detroit-Windsor border. Ticket holders are encouraged to phone the club today at 416-466-0313 for confirmation.

Singer-songwriter Nanci Griffith's concert at the Phoenix last night was cancelled, and promoters House Of Blues Canada cleared out of their downtown office for the day.

A number of smaller club gigs were also postponed or cancelled.

However, Lee's Palace and Horseshoe Tavern bookers Against The Grain Concerts were determined to proceed with their gigs as planned. Both last night's appearance by New York City hip-hop acts Cannibal Ox, Mister Lif and Aesop Rock, and tonight's show by electro-rockers Brassy were still on.

"Those bands epitomize New York and they're still playing," said Against The Grain's Ewan Exall. "As long as they can cross, our touring performers will play as scheduled. And the community of live music promoters will endeavour to ensure that the rock continues."

Anyone who is planning on attending a show would be advised to call the venue first.