Secretary of State Antony Blinken and Defense Secretary Lloyd Austin were appealing to the Senate Appropriations Committee for billions of dollars in military assistance to support Israel, Ukraine and other security costs.

Some two dozen spectators raised hands covered in paint in a symbol of the bloodshed in the Gaza Strip since Israel began its bombardment of the Palestinian territory after Hamas's attack earlier this month.

Several wore messages of "Free Gaza" written on their arms and held signs demanding "No more $$$ 4 Israel," while some cried out "Ceasefire now," "Palestinians are not animals" and "Shame on you all."

One man wore a shirt reading "Stop backing genocide."

Blinken was forced to stop speaking several times as some demonstrators were escorted out by police.

President Joe Biden has asked Congress for more than $105 billion in security spending, including $14.3 billion for its staunch ally Israel.

Israeli troops and Hamas militants were engaged in "fierce battles" in Gaza on Tuesday, Israel's military said, as tanks and armored bulldozers advanced through the ruins of the embattled territory, which the United Nations said is facing "unprecedented" humanitarian needs.

Israel's response to the Hamas attack has now killed more than 8,500 people, according to the latest count given by the Hamas-run health ministry, many of them children.

The siege comes after the bloodiest attack in Israel's history, when Hamas gunmen killed some 1,400 people in a brutal cross-border raid, according to Israeli officials.