More than 30 men attacked two guards and fled the Buimo Correctional Institution on yesterday afternoon, with the jail chief quickly alerting police who gave chase on foot, PNG commercial television network EMTV said.
"It is confirmed that 11 prisoners have been shot and killed and 17 wounded and recaptured," Lae Metropolitan Superintendent Anthony Wagambie told the broadcaster.
The PNG Today website said the escapees were high-risk prisoners serving time for offences including murder and rape.
Crime and lawlessness in PNG, a sprawling nation where many still live traditional and subsistence lives in remote areas, is rampant, with the World Bank saying in 2014 it was hampering the nation's economic development.