Dozens of parents who lost children in a quake-collapsed school knelt in front of a courthouse Tuesday, cradling portraits of the dead before police moved in and forcefully led them away.

The police action was the sternest response so far by authorities toward aggrieved parents who had been holding impromptu gatherings and memorial services to vent their anger over the deaths of their children.

The students' deaths have become the focus for Chinese, both inside and outside the quake zone, fueling accusations about corruption in school construction. The brewing public anger has become the biggest political challenge for the authoritarian government, threatening to turn popular sentiment even as it copes with aiding millions displaced by the disaster.

Thousands of students were killed in last month's earthquake, which had an overall death toll that rose to 69,107 on Tuesday. Angry parents and even rescuers have pointed to steel rods in broken concrete slabs that were thinner than a ball point pen among the 7,000 classrooms that were destroyed.

"Oh, my child!" one woman wailed as officers took the arms of the parents from Juyuan Middle School gathered outside the courthouse in this resort town. "Tell us something!" other parents shouted as they were led away.

As journalists were dragged up the courthouse steps by police — "For your safety!" they shouted — the parents from the school in nearby Juyuan were forced along the sidewalk and out of sight. Surrounded by police at a side entrance to the courthouse, they tried to present what some described as a lawsuit, saying they had no other option because local officials weren't responding.

The papers were refused, the parents said. Calls to local police were not answered.

"This wasn't a riot!" Zao Ming, an official from the foreign affairs office of the local government, said after the protest. "These people were just disrupting society. ... The government will solve their problems."

The government has taken some steps to try to help grieving parents. On Tuesday, Beijing began giving compensation to some families whose children died in the quake — about $144 per year to each parent who lost an only child. The Ministry of Civil Affairs also announced that parents who had lost their only child had first priority in adopting children orphaned by the disaster.

Meanwhile, relief efforts continued in the sprawling quake-hit area. Thousands of soldiers searched for a military helicopter that crashed near the epicenter on Saturday, with five crew and 14 injured quake victims aboard.

Authorities monitored the climbing water levels in a huge lake formed when a quake landslide blocked a river, the state-run Xinhua News Agency reported.

Suspicions between the government and grieving parents have grown since the quake. Plainclothes police roamed the grounds of the collapsed Xinjian — or New Construction — Elementary School in Dujiangyan during a memorial for International Children's Day on Sunday, one parent said.

They whispered into parents' ears: "Be careful what you say among the foreign media," said a father at the event, who only gave his surname, Yang.

Parents at the school said they scuffled with police Tuesday, after the authorities tried to block reporters from doing interviews.

"The police bent back the hands of some of the parents. It's too much!" said Chen Bijun, who lost her 12-year-old son in the school collapse.

Parents had arrived at the site Tuesday and found that authorities had removed their decorations of mourning and protest, replacing them with a single banner that said "Mourn the students who met grief." The parents immediately tore it down.

Both incidents happened Tuesday while Chinese leader Li Changchun, the country's fifth-ranked official, was touring other parts of the city, visiting survivors and relief workers, Xinhua said.

The Chinese government had been generally praised for its response to the earthquake, including the freedoms allowed both to foreign and domestic media.

In Beijing, Foreign Ministry spokesman Qin Gang said the "principle of transparency and openness remains unchanged." However, he also said local authorities were making decisions based on the conditions in the disaster zone, though "they are not trying to block any news or make difficulties for the reporters."

The Juyuan Middle School was sealed off with police tape Tuesday. "People can't come in, for their safety," a policeman at the school site said.

A short walk away from the school on Yongan Jie, or Forever Peaceful Street, Zhao Deqin sat in front of her temporary home — a tent — and held a photo of her twin daughters.

Zhao said all the school parents were behind the morning's effort to file a lawsuit. The government told them it wouldn't take the papers because it was doing its own investigation, she said. The parents still want an apology.

"I hope the government can reply," she said, adding that she will continue visiting the collapsed school every day because she can't stop herself from going.