OUAGADOUGOU, April 2 (Reuters) - Burkina Faso has expelled two French journalists working for newspapers Le Monde and Liberation, the two publications said on Sunday, accusing the authorities of seeking to stifle freedom of speech with an escalating crackdown on foreign media. Burkina Faso is one of several West African countries and former French colonies battling Islamist militant groups that took root in neighbouring Mali and have spread across the region over the past decade. See here for a complete list of exchanges and delays