Lawmakers also blamed Iran for arming Hamas militants, and questioned Egypt's role in that.
"My guess is there has to be some tacit involvement in Egypt and the border or these things wouldn't be getting in to Gaza," said Rep. C.A. "Dutch" Ruppersberger of Maryland, the top Democrat on the House Intelligence Committee.
Sen. Joseph Lieberman, I-Conn., said he thinks the threat of a ground war is overblown.
"I don't think the Israelis really want a ground war," he told "Fox News Sunday." ''They'll go into Gaza if they feel they need to, to eliminate the remainder of the missiles. ... So really, the decision is up to Hamas, as to whether there will be a ground invasion of Gaza or not."
Flaherty reported from Washington. Associated Press writer Gregory Katz in London contributed to this report.
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