BARCELONA, Spain – One hundred police officers took part Saturday in an anti-prostitution operation in downtown Barcelona that ended with 16 arrests along the landmark thoroughfare of Las Ramblas in the Catalan capital.

Besides the 16 people arrested, another 78 were identified.

Those taken into custody were two Nigerian prostitutes, two Brazilian transvestites and another 12 foreign citizens who are in Spain illegally, police officials said.

Taking part in the operation were agents of Spain’s National Police, the regional Catalan police and the Barcelona municipal force.

This police macro-operation is the first in which the three police forces have worked together and comes after a fierce controversy sparked by the publication at the beginning of this week of prostitutes photographed having sex in the middle of downtown Barcelona.

The interior ministry of the regional government of Catalonia promised to maintain until the end of autumn the police reinforcements that in recent days have succeeded in driving prostitutes out of Las Ramblas, one of the best-known areas of the Catalan capital that daily attracts thousands of tourists and visitors.

Aside from these recent brazen cases of street sex that offend against public decency, prostitutes in Spain, some 90 percent of whom are said to be illegal immigrants, are generally left to ply their trade. Brothels are outlawed but many “clubs” operate as such with little interference, according to the travel Web site gospainabout.com.

The site also says that many prostitutes double as pickpockets, especially in busy areas like the Gran Via in Madrid and Las Ramblas in Barcelona.