ISLAMABAD (AP) — Pakistan’s former Prime Minister Imran Khan postponed the resumption of his protest march on the country’s capital meant to challenge his successor’s government, his party said Tuesday.

Fawad Chaudhry, a senior leader in Khan’s Tehreek-e-Insaf party, said that instead of on Tuesday as previously announced, the march on Islamabad is now to resume on Thursday. He did not give any reason for the delay.

Khan, who began his protest march late last month in the city of Lahore with thousands of followers, was wounded in a shooting last week when a gunman attacked his convoy, killing one of his supporters. Thirteen other people were also wounded.

The gunman was arrested and has purportedly confessed to an assassination attempt on Khan, according to police. The attack has raised concerns about growing political instability in Pakistan, which has a history of political violence and assassinations.

Following the attack, Khan’s supporters have rallied across the country, at times clashing with police. On Monday, they blocked roads in the Pakistani capital and also in the cities of Lahore, Peshawar, Rawalpindi and elsewhere in the country.

Since the shooting, Khan has also claimed that Prime Minister Shahbaz Sharif and two powerful government and army officials were behind the assassination attempt, without offering any evidence. Authorities have rejected the claim.

Also Tuesday, Khan’s party criticized Sharif’s government after authorities charged the gunman with attempted murder, without investigating officials as the former premier had demanded and whom Khan accused of having links to the attack.

Khan was ousted from office in April in a no-confidence vote in parliament and has since been trying to stage a political comeback.