INDEPENDENCE, Mo. (AP) -- The Republican Party is tightening security at four Missouri phone banks after a break-in and theft of a laptop at one of the offices.

Police in the Kansas City suburb of Independence said Thursday that a rock was thrown through a window to gain entry to the McCain/Victory Office. A campaign staffer's laptop and satchel were taken between 10 p.m. Tuesday and 6 a.m. Wednesday.

The theft took place in the hours before GOP presidential nominee John McCain's speech Wednesday at the Truman Presidential Library and Museum in Independence, Truman's hometown.

Missouri Republican Party spokeswoman Tina Hervey said 24-hour security is being established at GOP offices in St. Louis, Independence, St. Charles and Springfield.

Hervey said the laptop contained information about areas that Republicans are targeting for support.

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