S&T Bancorp in Indiana, Pa., has agreed to buy DNB Financial in Downington, Pa.

The $7.2 billion-asset S&T said in a press release Wednesday that it will pay $206 million in stock for the $1.2 billion-asset DNB. The deal is expected to close in the fourth quarter.

The acquisition would allow S&T to enter the Philadelphia area, where DNB has 14 branches.

Buying DNB “dovetails nicely with our expansion into the central Pennsylvania market in 2015, and our overall strategic growth strategy focused on Pennsylvania, Ohio and New York,” Todd Brice, S&T’s CEO, said in the release.

S&T said it expects the merger to be accretive to its 2020 earnings per share.

DNB had been facing pressure from an activist investor in recent months.

CT Opportunity Partners I had been questioning DNB’s corporate governance and executive pay policies. The group, which owns nearly 6% of the company’s stock, had urged the board in January to hire an investment bank and consider selling.

Keefe, Bruyette & Woods and Wachtell, Lipton, Rosen & Katz advised S&T. PNC FIG Advisory and Stradley, Ronon, Stevens & Young advised DNB.