KIGALI (Reuters) - Rwanda began a week of solemn ceremonies on Sunday to commemorate the lives of 800,000 Tutsi and moderate Hutus murdered during the Rwandan genocide, a three-month-killing spree that began 25 years ago.

President Paul Kagame laid a wreath at the Gisozi genocide memorial site, where over a quarter a million of people are buried, before an afternoon of speeches and song. Later, a candelit vigil was held in the packed national soccer stadium.

“There is no way to fully comprehend the loneliness and anger of survivors and yet over and over again we have asked them to make the sacrifices necessary to give our nation new life. Emotions had to be put in a box,” Kagame said, his tall, thin form projected onto television screens around the nation.

“We are far better Rwandans than we were. But we can be even better still. We are the last people in the world who should succumb to complacency.”

The 100 days of slaughter began on April 6, 1994, after President Juvenal Habyarimana and his counterpart Cyprien Ntaryamira of Burundi -- both Hutus -- were killed when their plane was shot down over the Rwandan capital. The attackers have never been identified.

Among the legacies of the genocide is the International Criminal Court, which grew out of tribunals to investigate and prosecute those responsible for atrocities committed in Rwanda and during the Balkan wars of the 1990s.

At Gisozi on Sunday, popular Rwandan artists sang songs like “Turabunamira twiyubaka,” meaning “honoring them as we rebuild”.

“Remembering is necessary because it’s only thanks to looking back at what happened (that we can) ensure that it never happens again,” said hairdresser Olive Muhorakeye, 26.

In the late afternoon, thousands of people marched from parliament to the national soccer stadium. After they had entered, the lights were extinguished and the dark stadium was lit only by a sea of flickering candles as survivors spoke.

“I named my children after all my siblings that died,” Samuel Dusengiyumva told the emotional crowd, before praising the actions of the Rwandan Patriotic Front (RPF), a Tutsi-led rebel movement led by Kagame that ended the genocide. “I thank the RPF army that rescued us as the rest of world did nothing.”

As the testimonies continued, counselors in green jackets hurried through the rows of seats as some members of the crowd wept or screamed. Others took selfies.

NEIGHBOR TURNED ON NEIGHBOR

The downing of Habyarimana’s plane was immediately followed by killings as Hutu government soldiers and allied extremist militia began trying to exterminate the Tutsi minority.

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In villages across the densely populated country, neighbor turned on neighbor. Men, women and children were hacked to death, burned alive, clubbed and shot.

As many as 10,000 people were killed daily. Seventy percent of the minority Tutsi population was wiped out, and over 10 percent of the total Rwandan population.

The fighting ended in July 1994 when the RPF, led by Kagame, swept in from Uganda and seized control of the country.

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Under Kagame, any talk of ethnicity is strongly discouraged. The opposition says the tight control of the media and political sphere is also used to stifle dissent.

“The ruling party has decided to adopt dictatorship from early days after the genocide as they said they were protecting the national sovereignty, but now I feel that should end,” opposition figure Victoire Ingabire told Reuters.

“The government should let the opposition politicians work freely because denying them their rights will create problems. Twenty-five years is enough, the government should let people be free to express their opinions.”

Kagame, who won nearly 99 percent of the vote in 2017 polls on a 96 percent turnout, rebuffs such criticism, pointing to Rwanda’s strong economic growth and relative peace since the genocide. In Sunday’s speech, he also issued a challenge to anyone who might threaten the country.

“What happened here will never happen again. For those (who) ... want to mess with us ... we will mess up with them big time,” he said.