In a joint statement, major trade unions also accused Haryana government of "condoning the illegality being perpetrated by the management".
"We strongly protest against retrenchment of over 500 workers by the management illegally without giving any charge sheet or inquiry," it said.
"We demand reinstatement of workers so dismissed by the management and at the same time demand withdrawal of police force from within the premises of the factory," it added.
The statement was jointly issued by Centre of Indian Trade Unions (CITU), All India Trade Union Congress (AITUC), Hind Mazdoor Sabha (HMS), All India United Trade Union Centre (AIUTUC), All India Central Council of Trade Unions (AICCTU), Labour Progressive Front (LPF) and Self Employed Women's Association (SEWA).
Besides, Bharatiya Mazdoor Sangh (BMS), Indian National Trade Union Congress (INTUC), United Trade Union Congress (UTUC) and TUCC (Trade Union Coordination Committee) also signed the statement.
Condemning deployment of police at the plant, it said: "This has never happened in the history of India. The administration and police have come so shamelessly to meet the demand of the management.
"Instead of probing the circumstances leading to such an explosive situation, the police is busy subserving the interest of corporates".
