At least 19 people including a priest were killed at a Catholic church in Central African Republic.
The attack on May 1 by unidentified gunmen targeted the Church of Our Lady of Fatima in Bangui, capital of Central African Republic.
Nearly a hundred others were wounded when security forces tried to subdue the attackers.
Father Moses Otii, a priest at Our Lady of Fatima, was celebrating Mass with 2,000 parishioners on Tuesday, when the gunmen stormed the church compound.
Ottis said the attackers "outnumbered the police and the police retreated, then the attackers started shooting at the church and throwing hand grenades at the people."
"I saw three hand grenades thrown in front of the Church, but thank God in an area without people, and a grenade thrown in among many people gathered in the open air within the church's compound," Ottis told British-based Aid to the Church in Need.
Father Ottis said he was at the altar with other priests when gunfire erupted forcing people to panic.
"So many people were injured. They started running in all directions," Ottis described. "We had people almost everywhere – our rooms, refectory, parish halls, our kitchen, and even in the toilets."
Reports say many trapped churchgoers managed to escape through a hole in the church wall.
"Filled with panic, some Christians began to flee until bullets and grenades began to fall in the parish grounds, trapping those who remained in the compound," Moses Aliou, another priest at the church, told Reuters.
But others struggled to flee the mayhem.
"For example, a lady had both legs cut off by the grenade, she couldn't move. It was a commotion with people running and people crying," said Ottis.
Among the dead, Father Albert Tougoumale-Baba, who reportedly worked to increase harmony between Christians and Muslims in the community.
"I knew him well," Ottis shared with Aid to the Church in Need. "He was a calm speaker, he was in his 70s. He was someone joyful. He was lively despite his age."
The Central African Republic has faced years of ethnic and religious violence.
Major violence erupted in 2013 when Muslim rebels seized power in the majority-Christian nation. As a result, a band of Christian fighters formed to counter the Muslim rebels.
Thousands of people have been killed in fighting, including pastors, and several churches destroyed in the conflict.
This latest incident, which took place in a predominantly Muslim neighborhood, comes after 28 people where killed in clashes between security forces and Muslims fighters last month.
"In a country where the images from months of horrific violence are still fresh in the memories of people, these renewed tensions could stoke more attacks and bloodshed if those responsible are not stopped once for all," said Balkissa Ide Siddo, Amnesty International's Central Africa researche.
France condemned the attacks saying "those responsible for these criminal acts must be brought to justice."
Two Muslims were reportedly burned to death in reprisal attacks. A mosque and health facility were also attacked.
Calling for peace, Father Otii shared a prayer for his beleaguered country:
"Good Lord, bring us peace so that we can live like brothers and sisters together. Save all innocent people from their suffering," he shared with Aid to the Church in Need.
"Good Lord stop the violence and transform the hearts of those attackers. Come Lord, come to help us. May the blood of your servant Father Albert and all the innocent pour in this country not be in vain."
Central African Republic's president has called for three days of mourning to honor victims of Tuesday's attack.