WASHINGTON (Reuters) - The Committee to Protect Journalists and the U.S. government on Thursday condemned the harassment and assault of journalists during the Jerusalem Day flag march, urging Israel to protect reporters.

During the march, which commemorates the June 5 capture of East Jerusalem by Israeli forces in a 1967 war, Israeli settlers and far right protesters assaulted Palestinian freelance journalist Saif Kwasmi, who contributes to local agency Al-Asiman News, and Israeli journalist Nir Hasson, a reporter for the Israeli daily Haaretz, CPJ said in a statement, citing their employers.

Tens of thousands of flag-waving Israelis held the annual march on Wednesday. Police said 18 people, among them teenagers, were arrested, including for assaulting a journalist.

CPJ Program Director Carlos Martinez de la Serna said Israeli security forces "stood idly by" while protesters harassed and assaulted the journalists. CPJ urged Israel to probe the incidents and hold those responsible to account.

The U.S. State Department also urged Israel to protect reporters from such assaults.

"We have seen the videos of this incident. We have seen the photos of this incident. And we strongly condemn them," a U.S. State Department spokesperson separately told reporters. "We expect (Israel) to protect journalists from these kind of assaults."

Separately, the Israeli government has faced criticism from human rights and press advocates for the killing of over 100 journalists and media workers in its war in Gaza and for its ban on Al Jazeera operations in Israel. Israel denies targeting journalists and says its temporary ban on Al Jazeera was due to national security concerns.

(Reporting by Kanishka Singh in Washington; Editing by Daniel Wallis)

By Simon Lewis and Kanishka Singh