Asif Ali Zardari was taken to his home by police immediately upon landing in Pakistan. Reposrts are alternatively saying that he has been detained or merely deposited at his home:

Hundreds of PPP activists clashed with security forces at the Lahore airport in an attempt to meet their leader.

The airport was sealed off after the government issued a red alert on Friday night saying there was a terrorist threat.

Outside the airport police prevented any public movement and took into custody a number of PPP leaders including Makhdum Amin Fahim, who tried to gather there to welcome Zardari.

PPP headquarters here said over 15,000 PPP cadre have been taken into custody all over the country.

However, Pakistan Information Minister, Sheikh Rashid Ahmed denied reports that Zardari and other PPP leaders were arrested. “Zardari was not handcuffed neither he was arrested.”

Zardari was taken to his house by the police and left there, he said while complementing the police and the provincial Punjab government for preventing violent demonstrations during Zardari’s arrival.

Journalists are reporting that they were “roughed up” by police while waiting on the plane with Zardari. Zardari had planned to arrive via charter but changed to a regular flight after authorities barred his plane from landing.

Officials are stressing that Zardari is not under house arrest. But this account quotes and unnamed “high ranking police source” as saying other wise:

PPPP leader Asif Ali Zardari would be put under ???????house-arrest???????? after his arrival at Lahore airport on early Saturday (today), police sources said.
???????Zardari will be shifted to his cantonment residence (Bilawal House) soon after his landing at Lahore airport. City police has already cordoned off Bilawal House and he would not be allowed to participate in any rally or attend public gathering at Data Darbar???????, high-ranking police sources confided to The Nation on Friday.
Unfolding the security plan, the sources said that no less than 13,000 police officials of both the Investigation and Operation Wings had been deployed all over the provincial capital to keep the things under strict control on the arrival of PPPP leader Asif Ali Zardari, the husband of former Prime Minister Benazir Bhutto.
Thousands of policemen, sources say, have been deployed at all important city crossings, chowk and roads to implement Section 144 in the city. Heavy contingents of policemen have also been deputed at the roads leading towards Airport and no one will be allowed to move towards the airport on early Saturday, they added.
It may be noted that heavy contingents of the police have also been deployed around the leading shopping centres and multi-storey commercial centres to avoid any untoward incident on the occasion of Zardari????????s arrival in the city. More than 1,500 police officials including plainclothesmen have been directed to remain present in the limits of Allama Iqbal Airport. ???????They will also remain in constant touch with the top cops???????, sources maintained.
When asked that Asif Zardari is planning to attend a public gathering at Data Darbar, a senior police officer seeking anonymity, said ???????It is out of question. He will not be allowed to attend any gathering at Data Darbar or anywhere else???????.
The sources say that the Punjab government has strictly directed the city police to maintain law and order in the Provincial Capital and stringent action would be taken against the violators of the law. ???????No one will be allowed to take the law into hands???????, another police officer commented.