Tighter security at Boston 4th of July celebration

Massachusetts police are beefing up security for Boston's Fourth of July celebration, the first major public gathering since the Boston Marathon bombings.

Police are encouraging the public to attend the traditional music and fireworks show on the Charles River Esplanade, and say people shouldn't have safety concerns.

State Police Col. Timothy Alben says more video camera surveillance and more uniformed and undercover officers will be in place. Authorities will do bag searches and activate a text-a-tip line so people can pass on information about anything suspicious.

Backpacks are among the items authorities will prohibit along the Esplanade. Allowable items will also be restricted to chairs, tarps, and blankets no bigger than 10 feet by 12 feet after 4 p.m. in the Hatch Memorial Shell area, where the Boston Pops and others perform prior to the traditional firework display. 

Dzhokar Tsarnaev, the surviving suspect in the Marathon attack has reportedly told investigators that he and his brother Tamerlan Tsarnaev initially selected July 4 as the date to set off their improvised explosives, but accelerated their plans after the bombs were finished early. The April 15 bombings killed three people and injured more than 260. 

The Associated Press contributed to this report.