The sources said the bishop had gone to an airport to pick up some foreign friends. On leaving the airport and paying the toll, he and the driver of the car were stopped and arrested. His two foreign guests, French citizens, were also arrested, but released a few hours later.
News of Bishop Wei's arrest had provoked a strong reaction from the Holy See.
The director of the Vatican press office, Joaquín Navarro-Valls, said the Holy See was "worried and saddened" and asked Chinese authorities to reveal their accusations against the bishop "as occurs in any lawful state."
"The Holy See has no reason to doubt the bishop's innocence," Navarro-Valls said in a statement.
The next day an indirect response came from Beijing via the country's Foreign Ministry spokesman, who said that the prelate was being held "for questioning" about falsifying a document to leave the country.
Catholics in the Qiqihar Diocese feared the bishop would be released only after Easter in order to avoid unauthorized Holy Week gatherings and festivities.
Bishop Wei's sudden release on Sunday afternoon came as the National People's Congress was in session. The annual meeting of the Chinese Parliament found Chinese leaders debating whether to introduce the terms "freedom of faith" and "protection of human rights" into the country’s Constitution.
The bishop's release saves the government from embarrassment, as it is often criticized for stating things in theory but not backing them up in practice, AsiaNews reported today.
Other sources said the fact that foreigners were involved in the arrest facilitated the prelate's release.
According to AsiaNews, there are around 50 bishops and priests detained in Chinese prisons or prevented from practicing their ministry.
About 20 priests are in prisons or labor camps. Bishop James Su Zhimin and his auxiliary, Francis An Shuxin, from the Baoding Diocese, have spent the most time behind bars. Police arrested them in 1996.