A new website supporting legislation that would block the sale of firearms or explosives to individuals on the terrorist watch list was launched Wednesday by New York Mayor Michael Bloomberg and several others.

Bloomberg said he and more than 500 mayors have formed a coalition, Mayors Against Illegal Guns, to support a federal law to close what they call the terror gap, the ability of people on the terrorist watch list to buy firearms.

The group's website, www.TerrorGap.org, calls on Congress to enact laws that would ban those suspected of terrorist activities from purchasing firearms and explosives.

At least two bills have been introduced in Congress to accomplish the ban.

The website points to recent violent incidents that involved individuals who purchased guns despite being suspected of terrorist ties, including the Fort Hood shootings during which Major Nidal Hasan allegedly shot 43 people at his base.

The website invites visitors to sign a petition to support the legislation and provides updates about the mayors' actions.

Bloomberg, who co-chairs the coalition, testified before the U.S. Senate Committee on Homeland Security and Governmental Affairs Wednesday and urged Congress to pass such a bill.

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