Taking strong exception to the latest attacks on minorities, Bilawal said the "continuing attacks on minorities, if unchecked, would threaten the very existence of Pakistan".
In a statement issued in response to the two incidents, the nominal head of the ruling party urged political parties, religious groups and civil society organisations to "rise up to defend Jinnah's Pakistan that guarantees protecting fundamental rights of minorities".
He called on provincial governments and law enforcement agencies to do their best to protect the fundamental rights of minorities.
Attacks on temples, graveyards, properties and lives of the minorities are "an attack on Jinnah's vision of Pakistan and pose an existential threat to the country", he said.
A group of armed men vandalised some 120 graves at an Ahmadi cemetery in Lahore on Sunday.
The men, who belonged to a hardline sect, destroyed the headstones on the graves, saying they could bear Quranic inscriptions as Ahmadis were "not Muslims".
Pakistan's Ahmadis consider themselves Muslim but were declared non-Muslims through a constitutional amendment in 1974.
On Saturday, a builder demolished the century-old Shri Rama Pir Mandir and the nearby homes of several Hindu families in Karachi though the Sindh High Court is hearing a petition seeking a stay on any move to demolish the shrine.
Bilawal's father President Asif Ali Zardari has taken notice of the demolition and sought a report from authorities in Karachi.
Bilawal said in his message that his mother, slain former premier Benazir Bhutto, gave her life fighting the mindset that perpetrated actions like violence against the minorities.
"Our forefathers did not give their lives for an intolerant, extremist, sectarian and authoritarian Pakistan. I appeal you to rise up to defend Jinnah's Pakistan. I and my party will stand by you, shoulder to shoulder," he said.
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