Egyptian authorities will detain former presidential candidate Ahmed Shafiq for questioning in a corruption investigation if he returns from abroad, a judge said Wednesday.

Shafiq, ousted president Hosni Mubarak’s last prime minister, has been placed on a watch list at border points, Judge Osama el-Saeidy said in a statement.

Shafiq, who lost a presidential runoff vote against the Muslim Brotherhood’s Mohamed Morsi in June, left Egypt for Abu Dhabi two days after Morsi was declared president.

His aides have repeatedly denied that Shafiq is on the run, saying he would return soon to launch a new liberal political party, but the threat of arrest could deter him, analysts said.

“The investigative judge decided to put General Ahmed Shafiq’s name on the watch and travel ban lists based on investigations over his illegal allocation of 40,000 square meters of land . . . to Alaa and Gamal Mubarak,” Saeidy said.

Alaa and Gamal Mubarak, the former president’s two sons, are in prison facing corruption charges. Their 84-year-old father was sentenced in June to life in prison for the killing of protesters during the popular uprising last year that ended his 30-year rule.

Dozens of legal cases have been filed against Mubarak associates since the president was ousted Feb. 11, 2011.

The case against Shafiq was initiated in May by Essam Sultan, a leader of the Islamist al-Wasat party, who accused the former air force chief of having exploited his former position as head of the Young Air Force Officers Association to sell land owned by the association to Mubarak’s sons at reduced prices.

Shafiq denied the allegation and accused Sultan of being a former state security informant who had been used to spy on Islamists during the Mubarak era.

After Shafiq was put on the watch list Wednesday, Sultan said that he hoped he would return “to face a fair trial and present evidence on the accusations he made against me.”

One of Shafiq’s supporters, Ahmed Abdel Ghani, said the Muslim Brotherhood was behind the moves against Shafiq.

“I warn them to not touch General Shafiq when he comes back or else civil war will break out,” he said.

— Reuters

Tamim Elyan and Patrick Werr contributed to this report.