Television showed Liverpool striker Luis Suarez collecting some objects as he prepared to take a corner early in the match at Anfield.
Press Association Sport understands around a dozen coins were thrown from the Anfield Road End - part of which houses visiting supporters - during the first half.
Another object also appeared to be thrown towards the playing area as Liverpool captain Steven Gerrard celebrated scoring the first goal at that end.
No players were hit by any missiles.
Liverpool manager Brendan Rodgers said Suarez did not complain about any such issues.
Rodgers said: "He never mentioned nothing, no."
Liverpool went on to win the Barclays Premier League game 4-0 with two further goals from Daniel Sturridge and one from Suarez.