Pakistani police have kept up their siege around Imran Khan's home before a 24-hour deadline given to the ex-premier - to give up suspects allegedly sheltered inside - ends.
The siege and the authorities' demand for the suspects, wanted over violent protests over Mr Khan's recent detention, have angered the former prime minister's many followers and is raising concerns about more clashes between them and security forces.
Last week, Mr Khan's supporters attacked public property and military installations after he was dragged out of a courtroom and arrested.
At least 10 people were killed in clashes with police across the country.
The violence subsided only when Pakistan's Supreme Court ordered Mr Khan's release.
The popular opposition leader was freed from custody over the weekend and returned to his home in an upscale district of Lahore, Pakistan's second largest city and the capital of the Punjab region.
Dozens of his supporters have been staying there with him along with private guards.
Police, who on Wednesday surrounded the home, say they want 40 suspects to be handed over.
The ultimatum for Mr Khan ends at 2pm local time (10am UK time).
Usually, between 200 to 300 of Mr Khan's supporters, holding sticks, guard his residence around the clock, but most disappeared overnight.
Police have barricaded a key road leading to the house and asked residents to use an alternate route.
"Probably my last tweet before my next arrest," the 70-year-old former cricketer tweeted on Wednesday after the siege started.
"Police have surrounded my house."
Later, Mr Khan addressed his supporters, saying police can only search his house with a search warrant and "not barge in, creating chaos".
According to Amir Mir, a spokesman for the Punjab provincial government, police are ready to use firearms if attacked.
He told a press conference on Thursday at least 3,400 suspects linked to the clashes have been arrested and more raids are planned.
Pakistani authorities have said they will prosecute in military courts civilians involved in recent anti-government protests.
The announcement has drawn criticism from the advocacy group Amnesty International and the Human Rights Commission of Pakistan, which oppose trials of civilians in the military courts.
Military trials in Pakistan are usually held behind closed doors, depriving civilians of some of their basic rights, including contracting a lawyer of their choice.
Mr Khan was ousted after a confidence vote in Parliament last year.
He says his removal was illegal and a western conspiracy.
He now faces more than 100 legal cases, mainly on charges of inciting people to violence, threatening officials and defying a ban on rallies.
He also faces a graft case along with his wife and was summoned by the National Accountability Bureau to answer questions in connection with the case on Thursday.
However, Mr Khan is likely to ignore the summons from the anti-corruption authority to show up for questioning in the garrison city of Rawalpindi.
He is expected to address a rally of supporters on the outskirts of Lahore later in the day.