British officials are “very worried” about the kidnapped BBC journalist Alan Johnston after Hamas seized control of the Gaza Strip, where he is thought to be a prisoner.

Mahmoud Abbas, the Palestinian President, has reassured the UK Government for months that the journalist is safe and will be released, but the Fatah leader is no longer in control of the security situation in the coastal strip.

After a week of bloody factional fighting Hamas has seized control of Gaza from the pro-Abbas security forces. The President has declared a state of emergency and sacked the Hamas leader Ismail Haniya from his post as Prime Minister.

The Islamist organisation has vowed to secure the reporter’s release. “We will not allow his continued detention. We warn against not releasing him,” said Abu Obeid, a Hamas spokesman, at a press conference today.

Blockade drains life from Gaza

The movement of goods into Gaza had been intermittent at best since Hamas won Palestinian elections early last year

Multimedia

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Mr Abbas and his officials have been in contact with the kidnappers since Johnston’s abduction in March. It is unclear how this week’s violence will affect those negotiations, but Hamas have previously joined President Abbas in calling for his release.

Margaret Beckett, the Foreign Secretary, discussed Johnston’s well-being with President Abbas today, according to a senior official.

“We are very worried about (Alan Johnston’s) situation. The situation in Gaza now is very worrying from that point of view,” said a Foreign Office official.

Johnston, 45, from Argyllshire in Scotland, was kidnapped when he drove home from his office in Gaza City on March 12. He was the last remaining Western reporter permanently based in Gaza and he had entered the last few weeks of his three-year posting.

The BBC reiterated their concerns for his health today. “We are aware that the situation (in Gaza) is changing. We are working actively with everyone involved to effect Alan’s safe release,” said a spokeswoman.

The Islamist group Army of Islam released an undated video on May 1, showing Johnston for the first time since his abduction in Gaza.

The footage showed the journalist saying he was unharmed and delivering a highly political anti-Western message. The film also contained his captors’ demands for the release of prisoners held in the UK, including the radical cleric Abu Qatada.

Jaysh al-Islam (Army of Islam) is a radical splinter group led by one of Gaza's most ruthless criminal clans, the Dagmoush family. The organisation first surfaced in June 2006 when it claimed responsibility for killing two Israeli soldiers.

The group had earlier posted a video showing the reporter’s identity card and calling for Abu Qatada’s release.

The radical Islamic cleric was described by a Spanish judge as Osama bin Laden’s "spiritual ambassador in Europe". He is being held at Long Lartin high security prison in Worcestershire, awaiting the outcome of his appeal against deportation to Jordan.

The British Government accuses him of raising funds for extremist groups and offering "spiritual advice and religious legitimacy" to militants planning attacks.

Since Johnston went missing, his parents have continued to campaign on his behalf. A month after their son’s kidnap Graham and Margaret Johnston said: “Our son has lived and worked among the people of Gaza for the last three years to bring their story to the outside world and we ask everyone of them to help end this ordeal."

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