Pope Francis prayed on Sunday for victims of violence in the Central African Republic, where 27 people were kidnapped this week in an attack on a church which left 17 others dead.
He also called for greater efforts to be made to secure dialogue and peace in Ukraine, where an increasingly volatile conflict has seen European monitors detained by rebels in the country's restive east.
"It is with a very sad heart that I pray for the victims of continuing tensions in some regions of the Ukraine, and in the Central African Republic," Francis said after his Regina coeli prayer in St. Peter's Square.
"I renew my appeal to all those involved, that they may overcome misunderstandings and search patiently for dialogue and peace," he said.
On Friday, three people were killed in the capital of the Central African Republic just days after an attack on the Notre Dame de Fatima church, which left 17 people dead and saw another 27 kidnapped.
The deeply impoverished, majority Christian country has been wracked by relentless tit-for-tat attacks between Christian vigilante groups and the mainly Muslim ex-Seleka rebels who seized control in a coup last year, but were forced from power in January.
In Ukraine, the Organisation for Security and Cooperation in Europe said Friday it had been unable to establish contact with four of its monitors, while another four members detained by rebels in the neighbouring Donetsk region on Monday were still missing.
Moscow annexed Crimea earlier this year after protesters ousted Kiev's pro-Russian leadership.
More than 300 people have been killed in months-long fighting between Ukrainian troops and separatist insurgents in the country's east over the future of the ex-Soviet state.