Uber rival Lyft is seeking to raise at least $500 million in a new funding round, according to the Wall Street Journal.

Sources told the Journal that Lyft has been quietly pitching investors and is looking for a valuation of between $6 billion and $7 billion.

The WSJ said it could not learn when the fundraising started or which investors may be interested.

Lyft is the number two U.S. ride-hailing company behind Uber. Sources told CNBC in January Lyft could be profitable before its arch rival , given how much money Uber is spending to grow its international business.

Uber recently found itself mired in a series of controversies — including a highly publicized sexual harassment allegation by a former employee, a lawsuit from Alphabet's car company and CEO Travis Kalanick caught arguing with his Uber driver in a newly released video.

See the Wall Street Journal's full report on Lyft's fundraising plans here.