A man has reportedly been stabbed to death in front of shoppers at a major shopping mall in Sydney’s west.

Media reports say the stabbing occurred at Westfield Parramatta about 10.30am on Monday.

The incident allegedly happened on level four outside the Myer department store.

A witness told Macquarie Radio one man starting stabbing another man, then took off his shirt and lit a cigarette while waiting for police to arrive.

Several police are said to have Tasered the shirtless man, who had a large tattoo on his back, according to Macquarie Radio.

Shops in the Westfield centre near the alleged stabbing were reportedly forced into lockdown.

Myer and about 30 other stores are closed as a result of the fatal stabbing, a Westfield spokeswoman told AAP.

Level four and a part of level five are closed while police investigate the stabbing.

Counselling services are being provided by Westfield for employees, retailers, and customers.

She said Westfield will co-operate with police in their investigation.

The alleged stabber has reportedly been taken into custody.

AAP