Section 5 in The Code Of Criminal Procedure (West Bengal Amendment) Act, 1988
5. Amendment of section 245. -
In section 245 of the principal Act, after sub-section (2), the following sub-section shall be inserted:-"(3) If all the evidence referred to in section 244 are not produced in support of the prosecution within four years from the date of appearance of the accused, the Magistrate shall discharge the accused unless the prosecution satisfies the Magistrate that upon the evidence already produced and for special reasons there is ground for presuming that it shall not be in the interest of justice to discharge the accused.".
