Pakistani Prime Minister Nawaz Sharif has demanded to know why police apparently stood by while a pregnant woman was beaten to death by her family in front of one of the country's top courts.
Farzana Iqbal, 25, was attacked on Tuesday, police said, because she had married the man she loved.
Her husband said that police did nothing during the 15 minutes the violence lasted outside Lahore High Court.
"I begged them to help us but they said, this is not our duty," Muhammed Iqbal told Reuters. "I took off my shirt (to be humble) and begged them to save her."
In parts of Pakistan, a largely Muslim nation of 180 million people, women are expected to agree to arranged marriages and refusal can mean an "honour killing".
Many Pakistani families think it dishonourable for a woman to fall in love and choose her own husband.
Mr Sharif had taken notice of the "brutal killing" in the presence of police, his press office said in a statement, adding that a "totally unacceptable" crime had to be dealt with promptly by law.
"I am directing the chief minister to take immediate action and a report must be submitted by this evening to my office," it said, quoting Mr Sharif.
Police initially said Farzana had been stoned, but her husband said relatives had swung bricks, not thrown them.
All the suspects, except her father, who has been detained, have disappeared.
A police officer on Tuesday quoted the father as saying it had been an “honour killing”.
The 25-year-old had offended her family by marrying Mr Iqbal instead of a cousin selected for her.
Police said her father, two brothers and a former fiancé were among the attackers.
The attack happened near the gate of the heavily guarded court, one of the busiest roads in Lahore.
The couple had been due to testify there that morning that their marriage was genuine in response to a false charge of kidnapping brought by Farzana's family.
The case is the latest “honour killing” in Pakistan to outrage the world.
"I do not even wish to use the phrase honour killing," said UN High Commissioner for Human Rights Navi Pillay in a statement in Geneva.
"There is not the faintest vestige of honour in killing a woman in this way."
But for two days, the attack met with silence from Pakistani officials.
Most national media outlets gave little attention to the story. Honour killings are so common they usually only rate a paragraph or two.
Women have been mutilated and killed for wearing jeans, looking out of windows, singing or giving birth to girls.
The Human Rights Commission of Pakistan said there were 869 such attacks reported in the media last year - several a day. But the true figure is probably much higher since many cases are never reported.