PF Withdrawal before 5 years includes Employer & Employee contribution amount and Interest earned during period of service.
Interest earned on both employee’s contribution and employer’s contribution shall become taxable as ‘Income from other sources’.
Employers’ contribution by employer will become taxable "Income as Salary" at the time of withdrawal.
Employee’s Contribution shall become taxable as ‘Income from Salary’, if while making the investment you had claimed it as an investment deduction under section 80C. If not, then it won’t be taxable, since you would have had paid tax on it while making the investment.