Hayat Belkacem died and three other Moroccans were wounded -- one critically -- when a speedboat they were in was hit by live rounds on Tuesday in waters off the Moroccan locality of M'diq-Fnideq.

"There is no evidence at all to suggest that the passengers were a security risk to anyone - the only legal justification Morocco might have had to fire on them," Sarah Leah Whitson, Middle East and North Africa director at Human Rights Watch, said.

Morocco's navy found the boat acting "in a suspicious manner in Moroccan waters", according to a statement by the M'diq-Fnideq authorities, released by the interior ministry on Tuesday.

The vessel had "refused to comply with warnings", the statement said.

The Spanish driver of the boat was unhurt and was arrested, said the interior ministry, which announced an inquiry into the incident.

Human Rights Watch called for the investigation to begin immediately and urged the authorities to "disclose their findings publicly, and bring those responsible to justice".

Internet users shared pictures of the dead student and called her "Hayat the martyr", saying her only crime was attempting to leave a miserable life in Morocco to help her family.

"Moroccan civilians are killed in cold blood just because they want to leave this country of social disparities, poverty and repression", the Moroccan Association of Human Rights in coastal city Nador said on Wednesday.

Morocco -- a key route for sub-Saharan Africans trying to reach Europe -- said this month it has foiled 54,000 bids so far in 2018 by illegal migrants to cross the Mediterranean to Europe.

The figures included 7,100 Moroccans for the period until the end of August, according to figures released last week by the Moroccan government spokesman.

Since early 2018, Spain has recorded more than 38,000 arrivals by sea and land, according to the International Organization for Migration.