NEW YORK (Reuters) - An artists' collective took credit for exposing Donald Trump to unflattering scrutiny on Thursday, saying it was responsible for a life-sized nude statue of the Republican presidential candidate that turned up in a New York City park.

Copies of the orange-tinted likeness - featuring a massive belly, small fingers and missing some genital parts - were simultaneously unveiled in downtown Manhattan's Union Square Park and public places in four other U.S. cities.

The collective titled the work "The Emperor Has No Balls."

In New York, the unauthorized installation appeared to surprise passers-by - prompting stares, giggles and shrugs of bemusement from park visitors.

Ina Cope, a 58-year-old retiree from the Bronx borough of New York, said she was not expecting to see the Trump statue when she got off the subway to meet a friend for lunch.

"It was crazy: I was coming off the train, minding my own business, and there it was," she said, laughing.

By early afternoon, workers from New York's Department of Parks and Recreation had taken down the statue.

Mae Ferguson, a Parks Department spokeswoman, said the statue was removed because the installation of any unapproved structure is illegal in any city park.

The activist collective, a group called INDECLINE that includes artists, musicians and filmmakers, claimed ownership of the work, saying in an email that the statues were also placed in San Francisco, Los Angeles, Seattle and Cleveland. It said an artist called Ginger helped create the likeness.

"These fleeting installations represent this fleeting nightmare and in the fall, it is our wish to look back and laugh at Donald Trump's failed and delusional quest to obtain the presidency," INDECLINE said in a statement.

A Trump spokeswoman did not respond immediately to an email with a request for comment.

(Reporting by Chris Prentice in New York; Editing by Frank McGurty and Jonathan Oatis)