Cross-party group on tax calls for HMRC to act after Guardian investigation finds former Chelsea owner may owe up to £1bn

• Roman Abramovich may owe HMRC £1bn, analysis shows
• Revealed: how Abramovich dodged taxes on his fleet of superyachts

The government and HM Revenue and Customs should urgently examine whether Roman Abramovich owes British tax authorities up to £1bn, more than 40 MPs and peers have said, after an investigation by the Guardian and media partners found that his companies may have failed to pay tax on profits from an elaborate offshore investment scheme.

The intervention, from both Conservative and Labour MPs, comes after leaked papers and court filings shed new light on how the income from a $6bn (£4.8bn) cash pile amassed by the former Chelsea FC owner was managed.

Kizza Besigye, veteran opponent of President Yoweri Museveni, may face death penalty but will not get justice in military court, warns Winnie Byanyima, UNAids chief

It was a message from her sister-in-law asking where he was that made Winnie Byanyima start worrying about her husband, Dr Kizza Besigye, a prominent Ugandan opposition leader. Byanyima, head of UNAids, had just returned from Malawi to Geneva, where the UN programme on HIV/Aids is based, in November. She rang Besigye’s phone – it was off.

She made some calls and learned that he had gone from Uganda to neighbouring Kenya to attend a book launch. Then a journalist told her he believed Besigye was now being held in a military prison in Kampala, Uganda’s capital.