Portsmouth have signed Dagenham striker Oliver Hawkins, and brought in Cardiff midfielders Stuart O'Keefe and Matty Kennedy along with Burton defender Damien McCrory on loan.
Hawkins, 25, joins on a three-year deal for an undisclosed fee after netting 18 goals for the Daggers last season.
O'Keefe, 26, and Kennedy, 22, have joined Kenny Jackett's League One side for the remainder of the season.
McCrory, 27, joins until January having featured for Burton this season.
Find all the latest football transfers on our dedicated page.