Gaza's Hamas rulers issued an edict Wednesday banning journalists from working in the coastal strip unless they submit to sweeping press restrictions, and it said it would soon impose new restraints on public gatherings.

The moves, which follow the arrests of hundreds of opposition activists, appeared to be part of an intensifying clampdown after the Islamic militant group was confronted with a mass demonstration called by the rival Fatah movement that led to violence.

Monday's march by 250,000 Gazans was the biggest challenge to Hamas since its fighters seized control of the territory in June. Discontent is growing, in part because Israel's closure of Gaza's borders after the takeover has shut factories, cost thousands of jobs and driven up prices.

"The movement is under pressure, has lost its balance, and they are taking irrational decisions, such as restricting media coverage," said Hani al-Masri, an analyst in the Fatah-controlled West Bank. "This shows how deep the crisis is within Hamas."

The crackdown began toward the end of Monday's protest, when Hamas police fired on hundreds of people throwing stones. Eight civilians were killed and dozens wounded by gunfire.

Hamas later rounded up more than 400 Fatah activists, and it followed up Wednesday by announcing media restrictions and saying it planned to curb public assemblies.

Gaza's Interior Ministry said journalists who do not hold Hamas-issued press cards would not be allowed to work in the territory.

News organizations have resisted getting the cards because that entails submitting to restrictions which include a vague ban on stories that "cause harm to national unity" or do not uphold "national responsibilities."

The restrictions were first enacted in 1995 when Fatah was in power, and that group used the rules to crack down on Hamas.

"The government will not allow any reporter or photographer to work unless they get the press card," said a statement on the Interior Ministry's Web site. "This decision came after the rally of the Fatah movement in which dozens of cameramen and photographers were observed, not working for any media organization, but using these cameras for political parties and for personal reasons."

After the restrictions were issued, Hamas police briefly detained a Palestinian cameraman for Germany's ARD TV.

The cameraman, Sawwah Abu Sayef, said he was filming in the southern town of Khan Younis when he was escorted to a police station. He said he was asked whether he had a press card and whom he worked for. He was released after an hour.

Hamas issued a statement denying it detained the cameraman, saying police only asked a group of reporters to identify their employers.

The Tel Aviv-based Foreign Press Association, representing foreign journalists in Israel and the Palestinian areas, condemned what it called "harassment of Palestinian journalists in Gaza by Hamas security forces."

In a statement, the association also objected to the new rules. "The authorities in Gaza are urged to respect press freedom and to allow all journalists to pursue their work without intimidation or interference," it said.

Interior Ministry spokesman Ihab Ghussen said the government also planned to impose as yet undefined restrictions on "any rally, march or public event" in Gaza.

About 30 Fatah activists rounded up after Monday's protest were released Wednesday, including Mohammed al-Nahal, a party district leader in Gaza City.

Al-Nahal said he was held for 36 hours, smacked while blindfolded and asked to sign a paper saying he would adhere to the decisions of the government, including seeking permission for holding future rallies.

"I refused to sign and asked them to tell me if Fatah was a banned organization so I can convey the message to my leaders," he said. "They said no, it wasn't."

Hamas' drive to cement its grip on Gaza coincides with efforts by moderate Palestinian President Mahmoud Abbas and Israel to bridge differences ahead of a summit in the U.S. this month. The conference is aimed at relaunching peace talks and bolstering Abbas in his struggle with Hamas.

The two sides disagree on key issues, including the implementation of short-term peace obligations under the "road map" peace plan, which was dormant for years but is being revived by Washington.

The U.S. wants each side to meet obligations of the road map's first phase. That calls for Israel to freeze all settlement construction and dismantle dozens of West Bank settlement outposts, while the Palestinians are supposed to disarm militant groups and prevent attacks on Israel.

Palestinian negotiators contend they have started meeting their security obligations but say Israel has done nothing on its requirements.

The Israeli newspaper Haaretz said Wednesday that an Israeli delegation was going to Washington to negotiate with the U.S. on terms of a partial settlement freeze. That would contradict the road map, which says Israel must freeze all construction without exception.

Israeli government spokeswoman Miri Eisin said that "Israel is committed to fulfilling our side of the road map." However, she would not confirm whether Israel would halt settlement construction, even partially.

The U.S. consul general in Jerusalem, Jacob Walles, went for a firsthand look Wednesday at the performance of Abbas' security forces in the West Bank city of Nablus, a former militant stronghold was chosen as a test case by the Palestinian government for its forces.

"The Palestinian security forces have made some progress, and the condition in the streets is better," said Walles, who was accompanied by Palestinian Prime Minister Salam Fayyad.