Strikes in multiple neighborhoods across northern Gaza today have killed 42 people according to Gaza's Civil Defense. Videos from the immediate aftermath of the strike show an entire building leveled, children covered in dust.

A bombing of Al-Shati camp killed 24 people, a bombing in Al-Tufaah killed 18 people -- the number of casualties is likely to increase -- and a bombing in Al-Zaytoun killed 7 people, according to Civil Defense.

Fifty others were injured in the attacks, according to the Hamas media office.

Several others are still trapped under the rubble.

The Israel Defense Forces told ABC News they struck two Hamas military infrastructure sites in Gaza City.

House Speaker Mike Johnson wrote a letter to President Biden on Wednesday urging the president to "leverage all American options and influence to support Israel in bringing these hostages home."

"I write today to express grave concern that your administration is not taking sufficient steps to ensure the release of American hostages who are detained by Hamas." Johnson said. "The United States must do everything in our power to support Israel’s right to self-defense, and work toward the immediate release of hostages, including the remaining American citizens."

Johnson requested a briefing before July 10 on "the specific ways in which your administration plans to address the increasingly dire situation."

-ABC News’ Lauren Peller