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The gamma-ray blazar OJ 287 was in a high activity state during December 2015- February 2016. Coinciding with this high brightness state, we observed thissource for photometry on 40 nights in R-band and for polarimetry on 9 epochs inUBVRI bands. During the period of our observations, the source brightnessvaried between $13.20 \pm 0.04$ to $14.98 \pm 0.04$ mag and the degree ofpolarization (P ) fluctuated between $6.0 \pm 0.3$% and $28.3 \pm 0.8$% inR-band. Focusing on intra-night optical variability (INOV), we find a dutycycle of about 71% using $\chi^2$-statistics, similar to that known forblazars. From INOV data, the shortest variability time scale is estimated to be$142 \pm 38$ min yielding a lower limit of the observed Doppler factor$\delta_0 = 1.17$, the magnetic field strength $B \le 3.8$ G and the size ofthe emitting region Rs < $2.28 \times 10^{14}$ cm. On inter-night timescales, asignificant anti-correlation between R-band flux and P is found. The observed Pat U-band is generally larger than that observed at longer wavelength bandssuggesting a wavelength dependent polarization. Using V -band photometric andpolarimetric data from Steward Observatory obtained during our monitoringperiod we find a varied correlation between P and V-band brightness. While ananticorrelation is seen between P and V -band mag at sometimes, no correlationis seen at other times, thereby, suggesting the presence of more than oneshort-lived shock components in the jet of OJ 287.

Flux and polarization variability of OJ 287 during early 2016 outburst