Republican presidential candidate Donald Trump cited the shooting death of a relative of NBA star Dwyane Wade as a reason for black voters to support his candidacy.

In recent days, the real estate mogul has made increasingly explicit overtures to African-American voters to abandon their support of the Democratic Party, and by extension their backing for Hillary Rodham Clinton, the Democratic nominee.

In that vein, Trump—who has in part sought to cast himself as a "law and order' candidate who can tackle violent crime as well as illegal immigration—seized on the shooting of Wade's cousin as a call for black voters to back him.

Trump later followed up with a more sober post expressing sympathy with Wade and the family of the victim.

However, the reaction to his original tweet still lingered with many observers. It follows a speech he made just days ago, in which he said African-Americans had little to lose by switching from their traditionally solid support for Democrats. Trump has sought to make his case by saying that, over decades, progressive policies have failed blacks.

The mogul's comments also renewed a furious debate, both within and outside his campaign, about his discipline and a shoot-from-the hip style that raises questions about his temperament and judgment. In the glare of a general election, a few observers have argued Trump's reactions on Twitter to tragic events appear to sound offensive and self-serving.

Some political watchers have suggested that for the sake of the election, Trump's use of social media should be restricted, or at least tightly controlled.

Percolating in the background is the GOP's difficulty in reaching black and Latino voters. Republicans have a troubled history of reaching voters of color, but recent polls show Trump's support among blacks lingering in the single digits—lagging far behind the modest support of recent GOP nominees.

Trump's comments on Saturday were immediately denounced by many Twitter users, with political observers across the spectrum as opportunistic and tone-deaf.

Trump's remarks also converged with a brewing controversy over Maine Governor Paul Lepage, a prominent Trump supporter who earlier this week made comments perceived as racially insensitive.

However inadvertently, the furor shone a spotlight on one of the U.S.'s deadliest cities. Chicago is notorious for being a cauldron of deadly gun violence, which is among the highest in the country despite strict gun control laws. The city's murder rate has soared by more than 70 percent this year, and violent crimes are on track to set a new record in 2016.

Nykea Aldridge, Wade's cousin and a 32 year old mother of four, had recently relocated to an area on Chicago's South Side, according to a report in The Associated Press. She was near a school when two unidentified males fired at another man, but hit Aldridge instead.

On Twitter, Wade expressed his shock, and called for an end to Chicago's spiraling gun violence, but did not directly address Trump's remark.

Correction: An earlier version misspelled Dwyane Wade's name.

--The Associated Press contributed to this article.

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