I may be wrong but there is some irony in this. FIRSTLY, in the pics he looks more impressed than unimpressed, then spotted the cameras and changed the expression. SECONDLY, he called PETA after he was contacted by the Animal Activists. I hope I am wrong though.

*'Bullfights should be stopped!'  Matt Damon defends his attendance at Mexican arena

As an actor known for his humanitarian and charity work, eyebrows was raised when pictures emerged of Matt Damon at a bullfight earlier this week. 

However, the star has defended his attendance at the arena in Mexico, saying being at the event had only re-enforced his beliefs that 'bullfights should be stopped.'

According to Radar Online, the 41-year-old actor telephoned PETA (People for the Ethical Treatment of Animals) himself after the animal activists contacted him. 

Cultural experience: Matt Damon watched a bullfight at Mexico's La Monumental Bullring Stadium last Sunday 

'We wrote to Matt Damon as soon as pictures of him at a Mexican bullfight surfaced - and within 24 hours, he personally telephoned PETA Vice President Lisa Lange to correct the false impression that he had given,' Jane Dollinger from PETA told the website. 

'Matt said that he went to the bullfight believing that bullfights should be stopped but felt that he should see the cruelty for himself while he was in Mexico,' the spokesman added.

'He said that seeing with his own eyes what these tormented animals go through only reinforced an already strongly held belief that bullfights should be relegated to the history books.'

A face in the crowd: A casual Matt Damon blended in as he watched the event

Where's Damon? Matt watched the action in the ring from his stadium seat

'He also said that he was upset to think that his attendance was in any way construed to be an endorsement of such a barbaric activity.'

The controversial spectacle, in which bulls are baited in a ring for entertainment, took place in La Monumental bullring stadium in Mexico City.

Damon was seen blending into the crowd in a casual outfit of black baseball cap, hooded top and jeans. 

The PETA website describes bullfighting as  'inaccurate term for events in which there is very little competition between a nimble, sword-wielding matador (Spanish for 'killer') and a confused, maimed, psychologically tormented, and physically debilitated animal.'

Unimpressed: Damon yawns and takes a sip of his drink as he watched the fight 

Matt-a-dor: Damon watched the action unfold in the ring, although animal activists regularly condemn the practice

Animal movie: Matt stars alongside Scarlett Johansson in new movie We Bought A Zoo

The star was taking a break from shooting his new movie Elysium in Mexico.

He is said by the Hollywood Reporter to be playing an ex-convict in the film which is set to be released in 2013.

The movie's plot has been kept closely under wraps but is said to be set on another planet and also stars Jodie Foster and Diego Luna.

Damon will next be seen alongside Scarlett Johansson and Elle Fanning in film We Bought A Zoo which is released in the U.S. on December 23. 

The film is based on a memoir by Benjamin Mee about how the author and his family used their life savings to buy Dartmoor Zoological Park, a dilapidated zoo, replete with 200 exotic animals facing destruction, in the English countryside.

Family role: Matt plays a grieving widower who uses his savings to buy a dilapidated zoo