Celtic have signed Fulham striker Diomansy Kamara on loan until the end of the season and have the option to buy the player.
The 29-year-old Senegal international previously played under Celtic manager Tony Mowbray at West Brom.
He has won more than 40 caps for his country, scoring nine goals.
Mowbray has also completed the signing of Paul Slane from Motherwell. Despite his club's efforts to keep him, Slane, 18, joins Celtic on a four-year deal.
Motherwell are unhappy at losing a product of their youth system at such an early stage in his career.
A statement by Motherwell chairman John Boyle on the club website said: "We have tried and tried to get Paul to sign a long-term contract but much to our extreme disappointment, he has continually refused.
"We have offered the player improved competitive terms in line with other progressing youngsters at the club but both personally and through his agent, he has refused.
"Paul has been at the club for six years and we have financed his development and nurtured his talent, culminating in his senior debut at the end of last season.
"We have also stuck by and supported him over those years through both personal issues and injury and felt we were due some degree of loyalty for our efforts. Sadly he has chosen to refuse our offers and move on to Celtic."