Al-Jazeera, the pan-Arabic news channel, has always battled charges of bias, both from government officials in the Middle East and from those in Washington. But on Monday, the bias claims came from an unusual source: other Middle Eastern journalists.

In an unusual episode, al-Jazeera’s reporters were kicked out of a news briefing held by the Egyptian military in Cairo after the shooting of dozens of supporters of Mohammad Morsi, the nation’s ousted president. According to an Associated Press account, the al-Jazeera journalists left the meeting amid chants from the crowd of “Out! Out!”

The incident comes at a sensitive time for the satellite network, which is preparing to launch an ambitious news channel for American viewers. The channel, al-Jazeera America, will debut next month in about 50 million cable homes. It will replace Current TV, the low-rated channel that al-Jazeera purchased in January from former vice president Al Gore and other investors for a reported $500 million. Soledad O’Brien, the former CNN host and reporter, is among several high-profile American journalists hired by the channel.

Al-Jazeera’s rude reception in Cairo probably reflects a perception that has been building since even before Morsi and his political party, the Muslim Brotherhood, won and lost power in Egypt over the past year: that al-Jazeera and its owner, the royal family of the oil-rich Persian Gulf state of Qatar, have been supporters of Morsi and the Brotherhood. With Egypt now deeply divided, those alleged loyalties have cast al-Jazeera into disfavor among Egypt’s anti-Morsi faction.

An al-Jazeera spokesman, in an e-mail, called the expulsion of its journalists “intimidation” and denied any favoritism in its coverage. “We’ve always given all sides of opinion airtime on al-Jazeera. It’s our mantra,” said the spokesman, Osama Saeed. “As we saw at today’s astonishing press conference, though, large sections of the Egyptian media object to this open-minded ethos.”

Once hailed as a democratizing force in a region dominated by government-owned or -controlled news media, al-Jazeera’s independence from the politics of its Qatari owners has been challenged in recent years.

Many Western commentators noted al-Jazeera’s limited coverage of the uprising against Bahrain’s ruling family and its brutal suppression in 2011, contrasting it with its robust coverage of other popular revolts during the so-called Arab Spring. Qatar and Bahrain are close allies.

What’s more, “Al-Jazeera’s breathless boosting of Qatari-backed rebel fighters in Libya and Syria, and of the Qatar-aligned Muslim Brotherhood in Egypt, have made many Arab viewers question its veracity,” the Economist wrote earlier this year. “So has its tendency to ignore human-rights abuses by those same rebels. . . . ”

The magazine said that several of the network’s journalists, including star correspondents, have quit over political disagreements. Among them was Dave Marash, the former “Nightline” correspondent and WRC-TV anchor who quit in 2008 as an anchor for al-Jazeera English — the global, English-language spinoff of the Arabic channel — because of what he viewed as a “reflexive adversarial editorial stance” against Americans, primarily by the network’s British managers. Several staff members at al-Jazeera Arabic reportedly quit in protest on Monday over the network’s Egyptian coverage.

Al-Jazeera has “definitely taken the pro-Morsi side” in its Egyptian coverage, said Steven Stalinsky, executive director of the Washington-based Middle East Media Research Institute (MEMRI), an organization that monitors Arabic media and describes itself as nonpartisan.

He said the network’s management and journalists have long-standing ties to the Brotherhood; among others, its former chairman, Wadah Khanfar, was a member. Among its talk-show hosts is Yusuf al-Qaradawi, a Muslim cleric and Brotherhood adviser whom Stalinsky describes as “anti-Western, anti-Semitic and anti-American.”

Al-Jazeera’s opinion programs have been dominated by pro-Morsi pundits, and some of its journalists have openly supported the Brotherhood in postings on social media, said Mansour al-Hadj, who directs a MEMRI project on reform in Arab and Muslim countries.

But al-Hadj said he expects al-Jazeera America to take a more moderate tone, just as al-Jazeera English has moderated some of the political passions of the Arabic network. “I don’t think they’ll do the same thing” on the American network, he said. “It’s a different audience, and they need a different perspective. They’re not going to make fools of themselves by saying things that are misleading” or strongly partisan.

Philip Seib, author of “The Al Jazeera Effect,” a 2008 book about the network’s influence in the Arab world, concurs. Although the Arabic network “is perceived as strongly pro-Brotherhood,” the American version won’t be, he said.

“I don’t think you’ll see al-Jazeera America touting the Muslim Brotherhood,” Seib said. “It will be more like CNN. They want [the American channel] to be successful, and they know it can’t be a mirror image” of its Arabic and English-language forebears. All three are ”operating in their own political environments.”