The Foreign Office has said progress is being made in the search for five Britons kidnapped in northern Ethiopia.
A British diplomat in the capital Addis Ababa said they may have been abducted because of tensions in the disputed Eritrean border area.
The embassy staff and their relatives were sightseeing in the Afar region near Eritrea when they went missing.
The official did not give further details for fear of prejudicing the search, now in is seventh day.
Prayers
About a dozen friends of the kidnapped Britons gathered at St Matthew's Church, the only Anglican church in Addis Ababa to pray for them.
Since they went missing, the church has started opening its doors at 0800 (0500 GMT) for anyone who wanted to offer prayers.
Associated Chaplain, the Reverend Michael Starr, who led the prayers, told the Reuters news agency: "We are all shocked by what has happened. There are a number of people who are missing, five of them are connected with the British embassy.
"We are not allowed to reveal their names, so we do know some of them who are involved.
He added: "Our heart goes out to them, because they must be in awful difficulties. It is a very difficult place to live anyway. Of course being captive is a terrible thing."
Vehicles used by the Britons were found on Monday in the town of Hamedali, near the Eritrean border.
All appeared to have been damaged either by shrapnel or an explosion.
'Mistaken identity'
Eritrea has denied claims its forces took them over the disputed border, which is close to where the party disappeared.
The UK search team negotiated via satellite phone from the village of Berahle, about 37 miles (60km) from Hamedali, to gain access to the kidnap site.
The British ambassador to Ethiopia, Bob Dewar, said the group might have been the victims of "mistaken identity".
British diplomats carried out interviews with witnesses in the area in an effort to find out what happened.
One witness claimed "around 50 men" came into the Britons' camp in Hamedali on the night of the kidnap.
Relations between Ethiopia and Eritrea have been strained since Eritrea gained independence from Ethiopia in 1993 following a 30-year guerrilla war.