British athletics, still reeling from its summer drugs crisis, was rocked again yesterday after new figures revealed four more competitors were facing doping bans.

Statistics compiled by UK Sport divulged that three more athletes tested positive for anabolic steroids between April 1998 and March 1999, including another for nandrolone, and are having their cases reviewed. The fourth case involves a female athlete who refused to take a test.

Earlier this year, the former world and Olympic 100 metres champion Linford Christie was among three British athletes to test positive for nandrolone. Christie, the European 200m champion Dougie Walker and the 400m hurdler Gary Cadogan all pleaded innocent and were later cleared by UK Athletics, the governing body, of deliberately taking the performance-enhancing drug.

The new revelations, contained in the UK Sport Ethics and Anti-Doping Directorate's annual report, showed a record total of 11 positive tests - six for steroids, four for stimulants which carry only a public warning, and the athlete who refused to take a test. The figures include the cases of Walker and Cadogan but not Christie, who was tested in Germany.

One of the latest cases tested positive on two separate occasions for the body-building hormone testosterone but was cleared by UK Athletics. Just as in the cases of Christie, Walker and Cadogan, the International Amateur Athletic Federation is now investigating and may impose their own two-year suspensions.

Another tested positive for stanazolol, the drug discovered in Ben Johnson's urine when the Canadian was stripped of his Olympic 100m gold medal at the 1988 Olympics.

Three of the four cases involving stimulants were dismissed because the athletes involved were prescribed the drugs by their doctors. The fourth case involved a foreign athlete competing in Britain.

UK Athletics last night refused to disclose the identity of any of the latest batch, adhering strictly to their policy of confidentiality. "We are going through the disciplinary process and it is improper for us to release the name of any individual while this is going on," said Jayne Pearce, the spokeswoman for UK Athletics.

Meanwhile, world marathon record-holder Ronaldo da Costa has pulled out of this year's Great North Run after a kidnap threat, it emerged yesterday. Race chiefs said Ronaldo had told them that last week in his home country of Brazil there was an attempt by organised criminals to abduct him with the intention of holding him for ransom.