A chartered flight carrying 27 people deported by Germany and two from Poland landed in Islamabad, dpa news agency quotd Sheikh Naeem from the Federal Investigation Agency (FIA) that deals with immigration, as saying.
Immigration authorities released 10 of the deportees but arrested the rest for questioning, another FIA official Amjad Khan said.
They have been charged with leaving the country through illegal means including with the help of people smugglers, Khan said.
Rejected asylum-seekers and those who tried to enter the European countries on fake documents were among the deportees, the two officials said.
The FIA has arrested several dozen suspected people smugglers from Punjab province in the crackdown launched some three years ago.
Thousands of young Pakistanis try to reach countries like Germany, France, Italy and Spain every year in anticipation of a better future.
They pay millions to human traffickers to take them to Europe through a dangerous land and sea route that goes through Iran, Turkey and Greece.
Hundreds of illegal immigrants either die on their way or end up in jail in one of these countries.