In the wake of Tuesday morning's catastrophic terrorist attacks on the World Trade Center in New York and the Pentagon near Washington, D.C., several high-profile events — including the Latin Grammy Awards, the CMJ Music Marathon and concerts by Madonna, Tool, Janet Jackson and Slipknot — have been canceled or postponed.

The Grammy ceremony, which was to air live on Tuesday from the Forum in Inglewood, California, will not be rescheduled, an Academy spokesperson said. Artists scheduled to appear included co-host Christina Aguilera, Santana, Nelly Furtado, Jennifer Lopez, Luis Miguel, Juanes, Jon Secada, Thalia, Marc Anthony, Alejandro Sanz and Destiny's Child.

Major concert promoter Clear Channel Entertainment called off all its shows across the country for Tuesday, including concerts by Madonna, Weezer, Janet Jackson, Tool, Jimmy Eat World, Maxwell, Ozomatli and Dave Navarro.

It was not decided at press time whether Madonna's show at Los Angeles' Staples Center would be rescheduled. The two remaining dates of her Drowned World tour, at the same venue on Thursday and Friday, are scheduled to take place as planned.

Many Wednesday shows have been canceled, too, including concerts by Tool, Stevie Nicks, 98 Degrees, Stevie Nicks, Powerman 5000 and Crosby, Stills & Nash, according to the Clear Channel and Ticketmaster Web sites. Ticketmaster is posting a list of canceled and postponed shows at www.ticketmaster.com.

Slipknot and System of a Down's seven-week Pledge of Allegiance tour, scheduled to begin Friday in Rosemont, Ill., has been postponed until further notice, a publicist for Slipknot's label, Roadrunner, said on Wednesday. Rammstein, Mudvayne, No One and American Head Charge were also to be on the tour.

CMJ announced that its annual Music Marathon — which was to bring more than 1,000 bands to New York over four days starting Thursday — has been rescheduled for October 10-13. The festival lineup includes Coldplay, Ben Folds, the Strokes and many others.

Metropolitan Entertainment nixed concerts for Tuesday and Wednesday, including shows by O-Town and Lil' Romeo in New York.

Matchbox Twenty and Train's Tuesday show in Bossier City, Louisiana, was also postponed. Sting abbreviated his live concert webcast from Tuscany, Italy, because of the attacks, playing just one song, "Fragile," a Latin-tinged ballad that includes the lyrics, "nothing comes from violence/ And nothing ever could." The show was to have been recorded for a live album.

The House of Blues chain canceled all of its Tuesday shows and many scheduled for Wednesday, including appearances by Blink-182 and Crystal Method. The company is posting updates at hob.com.

The ticket on-sale dates for several U2 shows, scheduled for this weekend, have been postponed.

Television's Emmy Awards, scheduled for Sunday, were postponed indefinitely, while movie studios closed and Major League Baseball canceled all games scheduled for Tuesday and Wednesday.

(This story was updated at 3:59 p.m. ET Wednesday, September 12, 2001.)

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